In contrast to Scotland, early emigration from Ireland was motivated mainly by political and religious reasons. Beginning with the defeat of the Desmond rebellion in 1583, Irish refugees fled to Spain and Portugal. Some served in the Spanish Armada of 1588. Thousands fought for Spain in Flanders during the Thirty Years War. Owen Roe O’Neill and many who fought for the Confederate Catholics in the civil wars of the 1640s gained their military experience this way. By 1649 Tyrone’s regiment, formed in 1605, claimed to have suffered over 12,000 casualties in the service of Spain, most of them in battle. Throughout the seventeenth century a steady stream of exiles had made their way to the continent to serve in the Spanish, French and Austrian armies. Smaller numbers went to Bavaria and Russia. The flow increased after the Cromwellian conquest and again after the Irishjacobites were defeated in the Williamite War (1689-91). The English government did nothing to impede the flow of battle-hardened malcontents out of Ireland: it was glad to be rid of them and helped them on their way, allowing passage through England or even providing ships, as the Williamites did. Jacobite sympathisers, many of them from Munster, headed south to join Na Geanna Fiaine (the ‘Wild Geese’), as the Irish brigades in the service of Spain and France had become known. Motivated by the desire to fight the English and restore the Stuart dynasty, the Wild Geese distinguished themselves in many battles. Their most notable action was at Fontenoy (near Tournai in modern Belgium) in 1745, when a dramatic charge by the Irish brigades defeated British and Hanoverian troops under the duke of Cumberland. Ironically, the victory helped persuade Charles Edward Stuart to launch his ill-fated attempt to overthrow the Hanoverian dynasty later that year. It was 400 men of France’s Irish Brigade who provided the most professional unit of Charles Edward’s army and it was the one that fought hardest at Culloden.
Some Irish exiles rose high in foreign service: The Jacobite Charles Wogan became governor of La Mancha, and Alexander O’Reilly, who Joined Spain’s Hibernia regiment as a teenager, became the military governor of New Castile (Venezuela). Sometimes, changing political circumstances allowed military exiles to return - as happened after the restoration of Charles II - while those who settled overseas permanently did not form long-lasting Irish communities but integrated into local society (it did not help that most emigrants were male). Cambrai, Graz and Prague were known as popular retirement places for Irish officers. Later in the eighteenth century the British government began to discourage foreign recruitment in Ireland, since it needed the manpower for its own forces, and this together with a relaxing of discrimination against Catholics (after 1793 Catholics were allowed to hold commissions), and the availability of British colonies and the USA for emigration, led to the decline (but not the end) of the tradition of military emigration.
Emigration from Ireland increased steadily in the eighteenth century as around 250,000 Presbyterian Ulster Scots, disillusioned with the Anglican establishment and high rents, chose to leave for Britain’s North American colonies. With their ideals of self-reliance and hard work and their readymade frontier mentality, the contribution of Ulster Scots to the founding values of the United States was immense, yet today the Irish-American identity is overwhelmingly a Catholic one. Partly this has to do with numbers: Catholic Irish emigrants eventually greatly outnumbered Protestant ones. Mainly it has to do with alienation: Catholic Irish emigrants met the same discrimination in Protestant America that they had experienced at home. While Protestant Irish immigrants integrated easily into a society they had helped shape. Catholic Irish immigrants could not and, eventually, did not want to.