John Philip Holland (Irish: Seán Pilib Ó hUallacháin/Ó Maolchalann[citation needed]; February 24, 1841[1] – August 12, 1914[2]) was an Irish marine engineer who developed the first submarine to be formally commissioned by the US Navy, and the first Royal Navy submarine, Holland 1.

Initially working for an engineering firm, he returned to teaching again for a further six years at St. John's Catholic school in Paterson, New Jersey.

After his arrival in the United States, Holland slipped and fell on an icy Boston street and broke a leg.

While recuperating from the injury in a hospital, he used his time to refine his submarine designs and was encouraged by Isaac Whelan, a priest.

The Fenians (Irish revolutionaries), however, continued to fund Holland's research and development expenses at a level that allowed him to resign from his teaching post.

[9][10] After spending 56 of his 73 years working with submersibles, John Philip Holland died on 12 August 1914, in Newark, New Jersey.

A monument stands at the gates of Scholars Townhouse Hotel, Drogheda (the former building of the Christian Brothers school where Holland taught) in commemoration of his work.