Within easy reach of Brentford, in the neighbouring parish of Keston, is Oesterley Park, with the famous mansion named after it built by Sir Thomas Gresham, founder of the Royal Exchange, who more than once entertained Queen Elizabeth in it, and which was later owned by the wealthy London merchant, Sir Thomas Child, whose son Robert added two sumptuously decorated wings to it, and formed the nucleus of a fine collection of pictures by the old masters. More interesting than Oesterley House is the celebrated Syon or Sion House, standing in a charming park between Brentford and Isleworth, and occupying the site of a convent of the same name that belonged to a community of Brigittines, a branch of the Augustinian Order founded by St. Bridget of Sweden. This was one of the religious houses endowed, as already related in connection with Richmond, by Henry V. in expiation of his father's usurpation of the English throne, the foundation-stone having been laid by the king himself in 1431. It was originally situated in Twickenham, but soon became far too small for the accommodation of the many holy women who craved admission, and Henry VI. sanctioned the removal of the nuns to a larger house in Isleworth parish, the possession of which was secured to them by Act of Parliament. When or by whom the predecessor of the present Sion House was built is not known, but it is supposed to have been erected at the expense of the Brigittines themselves, who had been joined by many wealthy ladies, and it eventually became one of the richest religious communities of southern England. Many stories are told of the devotion of the sisters, and also, alas! of the decline of piety amongst them as time went on, rumours having even been circulated of gross misconduct amongst them. These were probably, however, mere idle tales purposely spread about by enemies; but there is little doubt that the downfall of the community was hastened by its abbess's espousal of the cause of the so-called Holy Maid of Kent, against whom Henry VIII. was bitterly incensed. In any case, Syon Monastery was one of the first of the great religious houses to be suppressed, and it was turned to account by the king in 1541 as a prison for Catherine Howard whilst her mock trial was going on. By a strange irony of fate her husband's body rested in the chapel—in which she had often prayed during the last few days of her life—on its way to be interred at Windsor, and, according to a gruesome tradition, blood suddenly flowed from it, a proof in popular belief that the queen had been unjustly condemned, and that Henry was indeed her murderer.

The nunnery of Sion and the manor of Isleworth were given by Edward VI. to the Protector Somerset, who at once pulled down the conventual buildings, using the materials for the foundation of the present mansion, that was still uncompleted when its owner's career was cut short by his attainder for high treason. The property then reverted to the Crown, and in 1553 it was given by the young king to John Dudley, Duke of Northumberland, who had been mainly responsible for the downfall of the Protector. The duke seems to have finished the work of his predecessor, for soon after he took possession of Sion House his son, Lord Robert Dudley, brought home to it his bride, the ill-fated Lady Jane Grey; and it was there that the crown was offered to her on the death of Edward VI. Thence the nine days' queen started by river in a state barge, attended only by a few adherents, on her fatal journey to the Tower, whence four months later she was led forth to execution, after having looked down from her window on the mangled remains of her husband as they were being carried away to their last resting-place.

After the death on the scaffold of the Duke of Northumberland Sion House once more reverted to the Crown, and Queen Mary gave it back to the Brigittines, but few of them cared to return to their transformed old home; and two years later even those few were driven forth again by Queen Elizabeth, who lent the house first to one and then another of her favourites. In 1604 the estate was granted by James I. to Henry Percy, Earl of Northumberland, who nearly lost it through his complicity in the Gunpowder Plot, for which he suffered many years' imprisonment and had to pay a fine of £11,000. He returned to Sion House only a short time before his death, bequeathing it to his son, Algernon Percy, who was made guardian of the children of Charles I., the Dukes of York and Gloucester and the little Princess Elizabeth, who died the year of her father's execution. The royal prisoners, for such they were, appear to have been very happy in their Isleworth retreat, for they were often allowed to go and see their father at Hampton Court, and it was not until they were taken to London to bid him farewell, just before his death, that they realised how terrible was their own position.

By the marriage between Lady Elizabeth Percy and Charles Seymour, Duke of Somerset, Sion House became the property of the latter, and during his ownership it was lent for a time to the Princess Anne, later Queen of England, who there gave birth to a son who lived for an hour only, one of her seventeen children, none of whom grew up. The son of Charles Seymour gave Sion House to his daughter Elizabeth in 1748, and her husband, Sir Hugh Smithson, having been created Duke of Northumberland, it passed back to the old earldom, and has ever since remained in the same family. It was the new duke who gave to the historic mansion the character that now distinguishes it, for he made considerable alterations and additions, entrusting the work to the then renowned architect, Robert Adam, who is said to have consulted Sir Horace Walpole, then living at Twickenham, on the subject of the internal decorations. The gardens, originally laid out by the Protector Somerset, and greatly improved by later owners, were still further enriched with rare plants; hothouses and conservatories were built, and the estate was converted into one of the most charming on the Thames, beautiful lawns, shaded by venerable trees, sloping down to the waterside. The massive quadrangular mansion, with a square tower at each corner, and a noble parapet, the eastern front surmounted by the venerable stone lion, the badge of the Percy family, that was long a familiar figure on the Strand front of the now demolished Northumberland House, rises up in quiet dignity from the park which, though it has none of the varied scenery of its rival at Richmond, is full of quiet charm.

Marble Hill

In addition to Sion House Isleworth still owns a few historic mansions, including Gumley House, named after a seventeenth-century owner; Shrewsbury House, once the home of Charles Talbot, Duke of Shrewsbury, both now convent schools; and Kendal House, long a noted place of entertainment, the last some little distance from the river, on the road to Twickenham. The church, said to have been designed by Sir Christopher Wren, though his plans were modified to save expense, is finely situated on a terrace looking down upon the Thames, and a wooded islet, presenting quite a picturesque appearance, especially when barges and other craft are waiting to be taken up or down stream by the tide. A little above Isleworth is the half-lock that has added so greatly to the usefulness of the upper river as a highway of traffic, and also to the healthiness of the districts on either side by keeping the mud constantly under water. Looking down upon it on the Middlesex side is the somewhat uninteresting suburb of St. Margaret's, occupying the site of the seat of the Marquis of Ailsa; and a little higher up stream is the beautiful park called Marble Hill, after the mansion still standing on it, that was bought in 1903 for the use of the public by the London County Council, aided by many private subscribers, including Sir Max Waechter, already mentioned in connection with the purchase of Petersham Ait. Marble Hill mansion is supposed to have been built in 1723 by Mrs. Howard, one of Queen Caroline's ladies-in-waiting, later Countess of Suffolk, after the designs of Lord Herbert, Earl of Pembroke, on a portion of the grounds of the neighbouring Orleans House, half the expense having been borne by George II. when he was still Prince of Wales. In laying out the grounds the owner had the benefit of the advice of Pope, then living at Twickenham, and also of Dean Swift, at that time in the service of Sir William Temple at Sheen, who is said to have prophesied that Mrs. Howard would certainly be ruined by her lavish outlay. That she was not is proved by the fact that she died at Marble Hill, leaving a fortune behind her; and later her old home was occupied by Mrs. Fitzherbert, who is said by some authorities to have been married in it to the Prince of Wales, later George IV., though others assert that the ceremony took place in her house in Park Lane. However that may be, she was certainly at her riverside home in 1795 when the wedding of her lover with the Princess Caroline of Brunswick took place, and she there held a little court of those loyal friends who believed in the legality of her union to the king.

Most picturesquely situated opposite the famous Petersham meadows and the no less celebrated Eel Pie Island, the resort on summer evenings of hundreds of pleasure-seekers, Twickenham, the name of which is supposed to have reference to the two streams that here flow into the Thames, was originally a hamlet of Isleworth that belonged, before the Conquest, partly to a monastery at Hounslow, and partly to the monks of Christchurch Abbey, Canterbury. On the suppression of the monasteries the property was added by Henry VIII. to the Hampton Court demesne; and later Charles I. gave the manor to Queen Henrietta Maria, to whom, after its temporary alienation by Parliament, it was restored on the accession of Charles II. The so-called manor-house of Twickenham, also known as Aragon Tower, occupies the site of an earlier building in which, according to tradition, Katharine of Aragon resided after her divorce; but the home of the Saxon owners of the property is supposed to have been in Twickenham Park, now built over, some authorities asserting that William the Conqueror himself lived in it for a short time. Whether this be true or not, there was not far from the first Sion House a mansion that belonged in the later sixteenth century to Lord Bacon, who entertained Queen Elizabeth in it in 1592. The brilliant prose writer was deeply attached to his Twickenham home, and grieved greatly when in 1601 he was compelled to sell it to meet his pressing necessities, receiving, it is said, only £1800 for it. During the next three centuries it changed hands again and again, and in 1803 its owner had it pulled down and sold the estate in plots for building. Its fate was later shared by many another historic home, but Cambridge House, named after the poet Richard Owen Cambridge, who occupied it for some years in the early nineteenth century, Orleans and York Houses still remain to bear witness to the days when Twickenham was an aristocratic suburb. The former is named after Louis-Philippe, who occupied it for some time when he was Duke of Orleans; the latter was for some time the property of Lord Clarendon, who settled it on his daughter, Anne Hyde, when she became the wife of James, Duke of York; and in it were born the Princesses Mary and Anne, who were both to become Queens of England.

A little higher up stream is a modern villa popularly known as Pope's, though as a matter of fact the house beloved of the poet, on which he lavished a fortune, was pulled down in 1807, and all that now remains to recall the time of his ownership is the subterranean passage leading from its grounds to the Teddington Road, that was once lined with an ornate shell grotto. It is fortunately far otherwise with the equally celebrated home of Horace Walpole, known as Strawberry Hill, that stands a little back from the river between Twickenham and Teddington, for though certain details have been modified it still retains the general appearance it presented when first completed by its owner. Originally a mere cottage, the future Strawberry Hill was bought by Walpole in 1747 from a certain Mrs. Chevenix, and the best years of the famous letter writer's life were spent in superintending its adornment. The guests he received at Twickenham included pretty well all the celebrities of the day, and his most important publications were issued from his private printing-press there. When on the death, in 1791, of his eldest brother's only son, he became Earl of Orford, he refused to take the title, preferring to remain plain Horace Walpole of Strawberry Hill; and before his death, which took place six years later, he bequeathed his beloved home to the sculptor Mrs. Damer in the hope that she would respect its traditions. In 1811 it became the property of the Dowager-Countess of Waldegrave, and since then it has changed hands several times, passing through various vicissitudes of neglect and restoration.