In 1773 the Duke of Leinster died, and his widow soon afterwards married William Ogilvie, who superintended Lord Edward's early education.  Joining the army in 1779, Lord Edward served with credit in America on the staff of Lord Rawdon (afterwards marquess of Hastings), and at the battle of Eutaw Springs (8th of September 1781) he was severely wounded, his life being saved by a recently-freed black slave named Tony, whom Lord Edward retained in his service till the end of his life.

In 1783 Fitzgerald returned to Ireland, where his brother, the duke of Leinster, had procured his election to the Irish parliament as member for Athy. In parliament he acted with the small Opposition group led by Henry Grattan but took no prominent part in debate. After spending a short time at Woolwich to complete his military education, he made a tour through Spain in 1787; and then, dejected by unrequited love for his cousin Georgina Lennox (afterwards Lady Bathurst), he sailed for New Brunswick to join the 54th regiment with the rank of major.

The love-sick mood and romantic temperament of the young Irishman found congenial soil in the wild surroundings of unexplored Canadian forests, and the enthusiasm thus engendered for the "natural" life of savagery may have been already fortified by study of Rousseau's writings, for which at a later period Lord Edward expressed his admiration.

In February 1789, guided by compass, he traversed the country, practically unknown to white men, from Frederickstown to Quebec, falling in with Indians by the way, with whom he fraternized; and in a subsequent expedition he was formally adopted at Detroit by the Bear tribe of Hurons as one of their chiefs, and made his way down the Mississippi to New Orleans, whence he returned to England.

Finding that his brother had procured his election for the county of Kildare, and desiring to maintain political independence, Lord Edward refused the command of an expedition against Cadiz offered him by Pitt, and devoted himself for the next few years to the pleasures of society and his parliamentary duties. He was on terms of intimacy with his relative C. J. Fox, with R. B. Sheridan and other leading Whigs. According to Thomas Moore, Lord Edward Fitzgerald was the only one of the numerous suitors of Sheridan's first wife whose attentions were received with favour; and it is certain that, whatever may have been its limits, a warm mutual affection subsisted between the two.

His Whig connections combined with his transatlantic experiences to predispose Lord Edward to sympathize with the doctrines of the French Revolution, which he embraced with ardour when he visited Paris in October 1792. He lodged with Thomas Paine, and listened to the debates in the Convention. At a convivial gathering on the 8th of November he supported a toast to "the speedy abolition of all hereditary titles and feudal distinctions," and gave proof of his zeal by expressly repudiating his own title - a performance for which he was dismissed from the army.

While in Paris Fitzgerald became enamoured of a young girl whom he chanced to see at the theatre, and who is said to have had a striking likeness to Mrs Sheridan. Procuring an introduction he discovered her to be a protégée of Madame de Sillery, comtesse de Geniis. The parentage of the girl, whose name was Pamela (?1776-1831), is uncertain; but although there is some evidence to support the story of Madame de Geniis that Pamela was born in Newfoundland of parents called Seymour or Sims, the common belief - that she was the daughter of Madame de Geniis herself by Philippe (Egalite), duke of Orleans - was probably well founded. On the 27th of December 1792 Fitzgerald and Pamela were married at Tournay, one of the witnesses being Louis Philippe, afterwards King of the French; and in January 1793 the couple reached Dublin.

Discontent in Ireland was now rapidly becoming dangerous, and was finding a focus in the Society of the United Irishmen, and in the Catholic Committee, an organization formed a few years previously, chiefly under the direction of Lord Kenmare, to watch the interests of the Catholics. French revolutionary doctrines had become ominously popular, and no one sympathized with them more warmly than Lord Edward Fitzgerald, who, fresh from the gallery of the Convention in Paris, returned to his seat in the Irish parliament and threw himself actively into the work of opposition.

Within a week of his arrival he denounced in the House of Commons a government proclamation, which Grattan had approved, in language so violent that he was ordered into custody and required to apologize at the bar of the House. As early as 1794 the government had information that placed Lord Edward under suspicion; but it was not till 1796 that he joined the United Irishmen, whose aim after the recall of Lord Fitzwilliam in 1795 was avowedly the establishment of an independent Irish republic.

In May 1796 Theobald Wolfe Tone was in Paris endeavouring to obtain French assistance for an insurrection in Ireland. In the same month Fitzgerald and his friend Arthur O'Connor proceeded to Hamburg, where they opened negotiations with the Directory through Reinhard, French minister to the Hanseatic towns. The duke of York, meeting Pamela at Devonshire House on her way through London with her husband, had told her that "all was known" about his plans, and advised her to persuade him not to go abroad. The proceedings of the conspirators at Hamburg were made known to the government in London by an informer, Samuel Turner. 

It is to our eternal discredit that this informer came from Newry. His original abode was a gentleman’s residence in Turner’s Glen – today known simply as The Glen, Newry.

Pamela was entrusted with all her husband's secrets and took an active part in furthering his designs; and she appears to have fully deserved the confidence placed in her, though there is reason to suppose that at times she counselled prudence. The result of the Hamburg negotiations was Hoche's abortive expedition to Bantry Bay in December 1796.

In September 1797 the government learnt from the informer MacNally that Lord Edward was among those directing the conspiracy of the United Irishmen, which was now quickly maturing. He was especially concerned with the military organization, in which he held the post of colonel of the Kildare regiment and head of the military committee. He had papers showing that 280,000 men were ready to rise. They possessed some arms, but the supply was insufficient, and the leaders were hoping for a French invasion to make good the deficiency and to give support to a popular uprising.

But French help proving dilatory and uncertain, the rebel leaders in Ireland were divided in opinion as to the expediency of taking the field without waiting for foreign aid. Lord Edward was among the advocates of the bolder course. His opinions and his proposals for action were alike violent. He was on intimate terms with proponents of assassination; there is some evidence that he favoured a project for the massacre of the Irish peers while in procession to the House of Lords for the trial of Lord Kingston in May 1798.

It was speculated that abhorrence of such measures converted Thomas Reynolds from a conspirator to an informer; at all events, by him and several others the authorities were kept posted in what was going on, though lack of evidence producible in court delayed the arrest of the ringleaders. But on the 12th of March 1798 Reynolds' information led to the seizure of a number of conspirators at the house of Oliver Bond.

Lord Edward Fitzgerald, warned by Reynolds, was not among them. The government were anxious to save him from the consequences of his own folly, and Lord Clare said to a member of his family, "for God's sake get this young man out of the country; the ports shall be thrown open, and no hindrance whatever offered." Fitzgerald with chivalrous recklessness refused to desert others who could not escape, and whom he had himself led into danger. On the 30th of March a proclamation establishing martial law and authorizing the military to act without orders from the civil magistrate, which was acted upon with revolting cruelty in several parts of the country, precipitated the crisis.

The government considered it had now no choice but to secure if possible the person of Lord Edward Fitzgerald, whose social position more than his abilities made him a most important factor in the conspiracy. On the 11th of May a reward of £1000 was offered for his apprehension. The 23rd of May was the date fixed for the general rising.  Since the arrest at Bond's, Fitzgerald had been in hiding, latterly at the house of one Murphy, a feather dealer, in Thomas Street, Dublin. He twice visited his wife in disguise; was himself visited by his stepfather, Ogilvie, and generally observed less caution than his situation required.

The conspiracy was honeycombed with treachery, and it was long a matter of dispute to whose information the government were indebted for Fitzgerald's arrest; but it is no longer open to doubt that the secret of his hiding place was disclosed by a Catholic barrister named Magan, to whom the stipulated reward was ultimately paid through Francis Higgins, another informer. On the 19th of May Major Swan and a Mr. Ryan proceeded to Murphy's house with Major H. C. Sirr and a few soldiers.  Lord Edward was discovered in bed.

A desperate scuffle took place, Ryan being mortally wounded by Fitzgerald with a dagger, while Lord Edward himself was only secured after Sirr had disabled him with a pistol bullet in the shoulder.  He was conveyed to Newgate gaol, where by the intervention of Lord Clare he was visited by two of his relatives, and where he died of his wound on the 4th of June 1798.  An Act of Attainder (repealed in 1819) was passed, confiscating his property; and his wife - against whom the government probably possessed sufficient evidence to secure a conviction for treason - was compelled to leave the country before her husband had actually expired.

Pamela, who was scarcely less celebrated than Lord Edward himself, and whose remarkable beauty made a lasting impression on Robert Southey, repaired to Hamburg, where in 1800 she married J. Pitcairn, the American consul.  Since her marriage with Lord Edward she had been greatly beloved and esteemed by the whole Fitzgerald family; and although after her second marriage her intimacy with them ceased, there is not sufficient evidence for the tales that represented her subsequent conduct as open to grave censure.  She remained to the last passionately devoted to the memory of her first husband; and she died in Paris in November 1831.  A portrait of Pamela is in the Louvre.  She had three children by Lord Edward Fitzgerald: Edward Fox (1794-1863); Pamela, afterwards wife of General Sir Guy Campbell; and Lucy Louisa, who married Captain Lyon, R.N.

Lord Edward Fitzgerald was of small stature and handsome features.  His character and career have been made the subject of eulogies perhaps beyond their merits.  He had, indeed, a winning personality, and a warm, affectionate and generous nature, which made him greatly beloved by his family and friends; he was humorous, light-hearted, sympathetic, adventurous.

But he was without the weightier qualities requisite for such a part as he undertook to play in public affairs.  Hotheaded and impulsive, he lacked judgment.  He was as conspicuously deficient in the statesmanship as he was in the oratorical genius of such men as Flood, Plunkett or Grattan.   One of his associates in conspiracy described him as "weak and not fit to command a sergeant's guard, but very zealous."

Reinhard, who considered Arthur O'Connor "a far abler man," accurately read the character of Lord Edward Fitzgerald as that of a young man "incapable of falsehood or perfidy, frank, energetic, and likely to be a useful and devoted instrument; but with no experience or extraordinary talent, and entirely unfit to be chief of a great party or leader in a difficult enterprise."

These, of course are subjective judgments of his personality and character. His place in Irish Republican history is assured.