The Clan/Sept History

Many variations of the name O Monahan have evolved since the time of its initial
creation. In Gaelic it appeared as O Manachain, which is derived from the word
"manach," which means "monk."

A name was often recorded during the Middle Ages under several different
spelling variations during the life of its bearer because literacy was rare
there was no real push to clearly define any of the languages found in the
Britsh Isles at that time. Variations found of the name O Monahan include
Monaghan, Monahan, Monagham, Monahon, Monagan, Mongan, Monaugher, Monck and many
more.
First found in county Roscommon, where they held a family seat from ancient
times.
Irish Families left their homeland in astonishing numbers during the 19th
century in search of a better life. Although individual reasons vary, most of
these Irish families suffered from extreme poverty, lack of work opportunities,
and exorbitant rents in their homeland. Many decided to travel to Australia or
North America in the hopes of finding greater opportunities and land. The Irish
immigrants that came to North America initially settled on the East Coast, often
in major centers such as Boston or New York. But like the many other cultures to
settle in North America, the Irish traveled to almost any region they felt held
greater promise; as a result, many Irish with gold fever moved all the way out
to the Pacific coast. Others before that time left for land along the St.
Lawrence River and the Niagara Peninsula, or the Maritimes as United Empire
Loyalists, for many Irish did choose to side with the English during the
American War of Independence. The earliest wave of Irish migration, however,
occurred during the Great Potato Famine of the 1840s. An examination of early
immigration and passenger lists has revealed many people bearing the O Monahan
name: William Monahan, who settled in Virginia in 1654; Edward Monaghan, who
arrived in New York, NY in 1806; Patrick Monagan, who arrived in Ontario in
1809.