The king of Naples had fitted out a fleet to go and attack the king of Sicily, who was a protector of the Ghibelines. Castruccio sent two desperate, but faithful fellows, to set fire to the ship in which the king himself sailed. The men got admittance on board the royal galley, which, swifter than the rest, sped on through the waves, while the rest of the fleet hung like a cloud on the far horizon. At night the smell of fire was perceived in the vessel, and a small flame issued from one of the windows: the affright and confusion were terrible, when they found that they were burning thus on the desert sea, while the other vessels were too distant to afford them aid. All hands were at work to extinguish the flames; and it was then that the hired incendiaries were perceived, as they tried to fire another part of the ship. It was found that they were provided with floats of cork, by which they hoped to preserve themselves in the water, until by some accident they might be rescued.

The fire was seen by the galley, in which the eldest son of king Robert was embarked, and which bore down to his relief. The youthful prince, in an agony of terror, lent his own hand to the oar that they might arrive more speedily. The whole crew was saved; and the criminals were reserved for torture and death.

The news of this detestable plot was spread through all Italy, nor was it much blamed. It was then that Euthanasia, the living spirit of goodness and honour, amidst the anguish that the unworthiness of Castruccio occasioned her, felt a just triumph, that she had overcome her inclinations, and was not the bride of a suborner and a murderer. Even now, remembering that it was known that she once loved Antelminelli, she was penetrated with shame, and her cheeks burned with blushes when she heard the tale. But, careless of an infamy which he shared with many of his countrymen, and sorry only that his design had not succeeded, Castruccio did not attempt to conceal the part he had taken in the plot, and loudly declared that all his enemies might expect the same measure as king Robert, while in return he permitted them to try the like arts against him.

In the mean time he prosecuted the war with redoubled vigour. In the winter of the year 1320, the Ghibelines reinforced their armies before Genoa, and called upon their allies for their utmost assistance; and Castruccio among the rest was to advance to their aid with all his forces. But the Guelphs were not idle: Florence had sent soldiers every campaign to reinforce the Genoese, and entered with spirit into all the enterprizes undertaken against the imperial party; although a wish to preserve their territory free from the horrors of war, and to repair by a long peace the injury done to their vines and olive woods, had caused them to preserve a shew of peace with Lucca.

Castruccio considered all his present successes as preliminaries only to his grand undertaking; and, having now reduced not only the territory of Lucca, but many castles and strong holds, which before had either been independent, or had paid tribute to Genoa, or to the lords of Lombardy, he planned a more vigorous system of warfare for the ensuing campaign. His first step was to increase his security and power in Lucca itself.

Having grown proud upon his recent successes, he began to disdain the name of consul, which he had hitherto borne. He assembled the senate; and, at the instance of his friends, who had been tutored for the purpose, this assembly bestowed upon him the government of Lucca for life, with the title of prince. He afterwards caused this grant to be confirmed by an assembly of the people; his warlike achievements, joined to the moderate expenditure of his government, had made him a great favourite with the inferior classes of the community, and they cordially entered into the projects of his ambition. Soon after, through the mediation of his friend Galeazzo Visconti, he obtained from Frederic, king of the Romans, the dignity of Imperial Vicar in Tuscany.

All this passed during the winter; and in the spring he assembled his troops, intent upon some new design. He had now been at peace with Florence for the space of three years, although, fighting under opposite banners, the spirit of enmity had always subsisted between him and them. Now, without declaring war, or in any way advising them of their peril, he suddenly made an incursion into their territory, burning and wasting their land as far as Empoli, taking several castles, and carrying off an immense booty; he then retreated back to Lucca.

This violation of every law of nations filled the Florentines at first with affright, and afterwards with indignation. They had sent their best troops to Genoa; and they found themselves attacked without warning or time for preparation. When the Lucchese retreated, anger and complaint succeeded. Castruccio replied to the reproaches of the Florentines by a declaration of war, and then immediately marched with his forces to join the besieging army before Genoa.

When the Florentines found that they could obtain no redress, they turned their thoughts to revenge. They raised what fresh troops they could among the citizens; and wishing to assist their small army by other measures which were then rife in the Italian system of warfare, they endeavoured to foment a conspiracy among the Lucchese for the overthrow of their prince's government. Castruccio received in one day letters from Giovanni da Castiglione, the general who commanded the few troops which he had left to guard his own principality, to inform him, that the Florentines had entered the Val di Nievole, burning and spoiling every thing before them; and from Vanni Mordecastelli, his civil lieutenant at Lucca, with information of a plot for the destruction of his power which was brewing in that city. Castruccio immediately left the Lombard army, and returned with his troops to disconcert these designs.

Of the castles which were situated within a circuit of many miles round Lucca, all were subject to Castruccio, except the castle of Valperga and its dependencies. He had often solicited Euthanasia to place her lordship under the protection of his government; and she had uniformly refused. The castle of Valperga was situated on a rock, among the mountains that bound the pass through which the Serchio flows, and commanded the northern entrance to the Lucchese territory. It was a place of great strength, and in the hands of an enemy might afford an easy entrance for an hostile army into the plain of Lucca itself. The Florentines, trusting to the affection which the countess bore their city, sent ambassadors to her to intreat her to engage in an alliance with them against Castruccio, and to admit a party of Florentine soldiers into her castle; but she rejected their proposals, and positively refused to enter into any league injurious to the existing government of Lucca. The ambassadors had been selected from among her intimate friends; and her Monualdo, Bondelmonti, was at the head of them: they were not therefore intimidated by one repulse, but reiterated their arguments, founded upon her own interest, and the service she would render to her native town, in vain. She felt that the liberty in which she had been permitted to remain, while, one after another, all the castles around her had been reduced, could only have arisen from the friendship and forbearance of the prince; and she judged that it would be a sort of treason in her, to take advantage of his moderation to introduce devastation into his country; at the same time she promised, that no threats or intreaties should induce her to ally herself with, or submit to, the enemy of Florence.