This wildness had profoundly alarmed his father, who for an Irishman was of a singularly peace-loving nature. He had early resolved that the boy should follow his own honourable profession, and Peter Blood, being quick to learn and oddly greedy of knowledge, had satisfied his parent by receiving at the age of twenty the degree of baccalaureus medicinae at Trinity College, Dublin. His father survived that satisfaction by three months only. His mother had then been dead some years already. Thus Peter Blood came into an inheritance of some few hundred pounds, with which he had set out to see the world and give for a season a free rein to that restless spirit by which he was imbued. A set of curious chances led him to take service with the Dutch, then at war with France; and a predilection for the sea made him elect that this service should be upon that element. He had the advantage of a commission under the famous de Ruyter, and fought in the Mediterranean engagement in which that great Dutch admiral lost his life.

After the Peace of Nimeguen his movements are obscure. But we know that he spent two years in a Spanish prison, though we do not know how he contrived to get there. It may be due to this that upon his release he took his sword to France, and saw service with the French in their warring upon the Spanish Netherlands. Having reached, at last, the age of thirty-two, his appetite for adventure surfeited, his health having grown indifferent as the result of a neglected wound, he was suddenly overwhelmed by homesickness. He took ship from Nantes with intent to cross to Ireland. But the vessel being driven by stress of weather into Bridgewater Bay, and Blood's health having grown worse during the voyage, he decided to go ashore there, additionally urged to it by the fact that it was his mother's native soil.