In 1744 he commissioned a new French
privateer the
Du Teillay (18 guns), in Nantes. She played a central role in the
Jacobite rising of 1745, ferrying
Charles Edward Stuart to
Ardmolich with supplies and funds to support his cause. He took a leading role in the French Irish community's financing and planning and of Charles's expedition to Scotland, the 1745 Jacobite rising, and was a key figure in all aspects of the naval side of the rebellion. In his correspondence with the Prince, Walsh adopted the pseudonym Monsieur Le Grand and the young prince was called Mr Douglas; they also had face-to-face planning meetings at
Navarre in April 1745. Antoine accompanied the Prince on the journey on board the
Du Teillay (Captain Claude Durbé) on 7 July at Saint-Nazaire and they were joined by French escort warship the L'Elisabeth, bound for
Ardmolich in Scotland. Two days later on the 9 July 1745 they were intercepted off
the Lizard by
HMS Lion, and were severely impeded in their mission when they exchanged fire, the Elisabeth was so badly damaged she had to return to port taking the arms and Irish volunteers with her. The
Du Teillay and was obliged to continue alone eventually arriving at
Eriskay in the
Outer Hebrides on 2 August, they then sailed onto Loch nan Uamh and two days later Antoine had to take his leave for France, leaving Charles with his eight companions to proceed to
Glenfinnan where on 19 August 1745 he raised his
Standard, despite having no money and no supplies. In the same year Antoine's second son, Antoine Jean Baptiste Walsh (1745–1789) was born. James III (
James Francis Edward Stuart), the Prince's father, created him an Earl Walsh in the
Jacobite peerage of
Ireland on 20 October 1745. After Culloden, on 16 April 1746 Walsh sent detailed proposals to
Maurepas the French minister of marine for rescuing the prince, some of which was acted upon, however following risings failure he had fallen out of grace with the French court. Coincidentally Charles was to return to Loch nan Uamh by the 20 September 1746 to the nearby
Prince's Cairn, which marks the spot where he finally left Scotland forever on a French ship after the unsuccessful rebellion. He sufficiently had recovered favour at court to be ennobled by
Louis XV in December 1753. ==Château de Serrant==