In the Virginia of England's rule, the vestry of a Parish "divided with the County Court the responsibility of local government, having as their especial charge the maintenance of religion and the oversight of all things pertaining thereto in the domain of charity and morals."[74] The parish was a territorial subdivision with large civil as well as ecclesiastical powers and duties and when, through increasing population, a parish came to be divided, in those days of expanding settlement, it usually was followed by the creation of a new county. As has been noted in a prior chapter, Truro Parish, then coextensive with Fairfax County, was divided in 1748 by the Assembly setting off the upper part thereof, above Difficult Run, as Cameron Parish, thus indicating the early organization of a new county. But the politicians of Tidewater were beginning to look askance at the rapid increase of new counties in the upper country, fearing a diminution of their influence and control and perhaps there was some opposition in Fairfax itself. A petition presented to the Assembly in 1754 by the people of Cameron that they be formed into a new county resulted in a bill being passed to that end which, however, was disapproved by the Council. Again a petition was presented to the next Assembly with no better success; but on the 8th day of June, 1757 a bill was passed creating the new county. It reads as follows:

"An Act for Dividing the County of Fairfax

"I. Whereas many inconveniences attend the upper inhabitants of the County of Fairfax by reason of the large extent of said county, and their remote situation from the court house, and the said inhabitants have petitioned this present general assembly that the said county be divided: Be it, therefore enacted, by the Lieutenant-Governor, Council and Burgesses of this present General Assembly, and it is hereby enacted, by the authority of the same, that from and after the 1st day of July next ensuing the said county of Fairfax be divided into two counties, that is to say: All that part thereof, lying above Difficult run, which falls into the Patowmack river, and by a line to be run from the head of the same run, a straight course, to the mouth of Rocky run, shall be one distinct county, and called and known by the name of Loudoun: And all that part below the said run and course, shall be another distinct county, and retain the name of Fairfax.

"II. And for the due administration of justice in the said county of Loudoun, after the same shall take place: Be it further enacted by the authority aforesaid, that after the first day of July a court for the said county of Loudoun be constantly held by the justices thereof, upon the second Tuesday in every month in such manner as by the laws of this colony is provided, and shall be by their commission directed.

"III. Provided always, that nothing herein contained shall be constructed to hinder the sheriff or collector of the said county of Fairfax, as the same now stands entire and undivided, from collecting and making distress for any public dues, or officers fees, which shall remain unpaid by the inhabitants of said county of Loudoun at the time of its taking place; but such sheriff or collector shall have the same power to collect or distrain for such dues and fees, and shall be answerable for them in the same manner as if this act had never been made, any law, usage or custom to the contrary thereof in any wise notwithstanding.

"IV. And be it further enacted, by the authority aforesaid, that the court of the said county of Fairfax shall have jurisdiction of all actions and suits, both in law and equity, which shall be depending before them at the time the said division shall take place; and shall and may try and determine all such actions and suits, and issue process and award execution in any such action or suit in the same manner as if this act had never been made, any law, usage, or custom to the contrary in any wise notwithstanding.

"V. And be it further enacted by the authority aforesaid, that out of every hundred pounds of tobacco, paid in discharge of quit rents, secretary's, clerk's, sheriff's, surveyor's, or other officers fees, and so proportionately for a greater or lesser quantity, there shall be made the following abatements or allowances to the payer, that is to say: For tobacco due in the county of Fairfax ten pounds of tobacco, and for tobacco due in the county of Loudoun twenty pounds of tobacco; and that so much of the act of the assembly, intitled, An Act for amending the staple of tobacco, and preventing frauds in his Majesty's customs, as relates to anything within the purview of this act, shall be and is hereby repealed and made void."[75]

The boundaries of the new county thus fixed have since that time been changed but once, when in 1798, a part of the originally constituted Loudoun was, by act of the Legislature, returned to Fairfax as later will be noted.[76]

Thus, from the formation of Northumberland County in 1647, it had taken 110 years for a sufficient population to penetrate, settle and develop in the backwoods to justify the organization of Loudoun. At first the creation of new counties out of the early Northumberland had been rapid. Lancaster along the Rappahannock was formed in 1651 and Westmoreland along the Potomac in 1653. Out of Westmoreland came Stafford in 1664. Then, so far as the line of descent of Loudoun is concerned, there is a long wait. Indian warfare and Indian domination of the upper country effectually held back settlement until Spotswood's epochal treaty of 1722. With the withdrawal of the Indians the pressure from Tidewater rapidly had its effect. Out of the Stafford "backwoods" and those of King George to the south was organized in 1731 Prince William with a disputed western boundary, the Proprietor claiming much of the Shenandoah Valley and the Virginia government holding to the Blue Ridge but the act discretely leaving that question untouched. In 1742 the territory above "Occoquan and Bull Run and from the head of the main branch of Bull Run by a straight course" to Ashley's Gap became the County of Fairfax of which, as shown, Loudoun in 1757 was born. Her contiguous county Fauquier was, by contrast, taken directly from Prince William in 1759.

It would have been wholly appropriate to have named the new county Lee or Carter, honoring families and individuals which had been so active in its development but the Lees then loved the Carters not at all nor the Carters the Lees and doubtlessly each would, and perhaps did, prevent the honor going to the other. So it came about that the lusty infant became the namesake of a man whose fame, so far as Virginia and the other American Colonies were concerned, was highly ephemeral. On the 17th February, 1756, in the winter following Braddock's defeat, John Campbell, fourth Earl of Loudoun, had been appointed Captain-General and Governor-in-Chief of Virginia and, on the 20th of the month following, Commander-in-Chief of the British forces in America. He seems to have owed his selection to his own and his family's influence with Court and ministry; certainly nothing in his earlier career had logically earned the bestowal of a paramount command in such a critical period for Britain. Loudoun, the only son of the third Earl of that ilk and his wife the Lady Margaret Dalrymple (only daughter of John 1st Earl of Stair) had been born in 1705 and succeeded his father in the title and estates in 1731. From 1734, until his death in 1782, he was one of the representative peers of Scotland. At the age of twenty-two he entered the army and had been appointed Governor of Sterling Castle in 1741, becoming aide-de-camp to the king in 1743. When the Jacobite rebellion broke out in 1745 he had been a staunch supporter of the House of Hanover, raising a regiment of Highlanders of which he became colonel and which later was cut to pieces at the Battle of Preston. Loudoun was one of the few who came out of the fight unscathed and, shewing that upon occasion he was capable of energy as well as loyalty, promptly he raised a force of more than two thousand new soldiers.