John O'Sullivan (soldier)

Sir John William O'Sullivan (1700 - c.1760) was an Irish soldier in the service of France. He was born in County Kerry in 1700 and educated in Paris and Rome, being intended for the priesthood. He returned to Ireland upon the sudden death of his father and, being unable to retain his parental estates due to the Penal Laws, he chose to forfeit them and made his way back to France where he joined the army eventually rising to the rank of colonel.

Early career
According to A Compendium of Irish Biography: "He ... rose rapidly, and was coadjutor of Jean-Baptiste Francois des Marets, marquis de Maillebois in the atrocious suppression of liberty in Corsica in 1739. There and on the Rhine he earned the reputation of an able captain in guerrilla warfare".

However, by the time of the Battle of Culloden it was said of O'Sullivan that: "his vanity is superseded only by his lack of wisdom."

It was probably his reputation gained in the Corsican theatre that brought him to the attention of Prince Charles Edward Stuart, who chose him as his adjutant and quartermaster-general during his campaign in Great Britain, the Jacobite Rising of 1745. O'Sullivan was constantly at Prince Charles' side from when the prince landed in Scotland on 23 July 1745, to his escape on 1 October 1746, escaping in a French frigate, the L'Heureux captained by his fellow-Irishman, Antoine Walsh.

Battle of Culloden
Despite the fact that Lord George Murray was far better suited to commanding the Highland Clan Army in the battle, having a better understanding of suitable ground, tactics and utilization of his men, and notwithstanding that he had twice defeated government forces of superior numbers, it was O'Sullivan who Prince Charles turned to when the plan of battle was formulated. This led to quarrels between Lord George and the prince over the chaos in the army's administration and the choice of the ground for the battle, which had been chosen by O'Sullivan.

In short, the ground could not have been worse for the Jacobite Army. Flat, open, treeless, devoid of shelter and ideal for the deployment by the Government forces of its cannon and cavalry. The battlefield was bordered by two walls, but despite the appeals from Lord George to have these demolished (fearing both crossfire and outflanking), O'Sullivan refused the request. It was said that O'Sullivan hadn't even inspected the ground, deeming it "unnecessary" and believing it to be a "good field". In the days leading up to the battle further chaos within the Highland Army had ensued. Despite his position as the army's quartermaster-general, O'Sullivan had failed to provide the correct type of ammunition for its small number of cannon. In addition, food rations were meager or non-existent leading to many within the Jacobite Army having not eaten for two days prior to the battle. What amounted to rations had been left behind with the army's small stock-pile of ammunition in Inverness.

Allied to this was the infamous "night march" which had taken place the night before the battle, resulting in the exhaustion of the Jacobite Army and further leading to a state of confusion when it was time for the army to be drawn up for battle, with resentment within the army being created by not allowing the Clan McDonald to stand on the right in the line of battle (as was their ancient right since Bannockburn). However, there is a degree of contention regarding this. In Bonnie Prince Charlie in Moidart, 1745-46, Tim Roberton asserts that the orders were from Lord George Murray and not from O'Sullivan. This is further supported in Culloden Moor and the Story of the Battle, in which it states that Lord George Murray alleged that Montrose had assigned the right to the Athol Highlanders. The Prince declined to decide on a matter on which he felt imperfectly informed. He, however requested the MacDonald chiefs to concede the point on this occasion, which they agreed to do; but their followers were not reconciled to the arrangement.

Ranged against the disciplined, rested and well nourished troops of the Duke of Cumberland and his Government forces, the outcome was inevitable. Whilst the entire blame cannot be directed at O'Sullivan alone, his numerous shortcomings can be seen as very much a contributory factor.

Post-Culloden
Despite the catastrophe at Culloden, O'Sullivan remained one of Prince Charles' most trusted advisers, and the prince's subsequent escape was due in a great measure to his energy and tact. O'Sullivan was knighted by James III.

Further information regarding O'Sullivan is sparse. However he married Louise Fitzgerald in 1749 with whom he had a son, Thomas O'Sullivan, who went on to become a Major in the Irish Brigade.

Sir John O'Sullivan is thought to have died in the early 1760s.