The Clan/Sept History

The Irish name MacGeraghty was originally written in a Gaelic form as Mag
Oireachtaigh, which is derived from the word "oireachtach," referring to a
member of an assembly.

Names from the Middle Ages demonstrate many spelling variations. This is because
the recording scribe or church official often decided as to how a person's name
was spelt and in what language. Research into the name MacGeraghty revealed many
variations, including Gerrity, Gerty, Gerighty, Gerighaty, Gerety, Gerahty,
Garraty, Geraty, Jerety, McGerity, MacGeraghty, MacGartie, MacGarty and many
more.
First found in counties Roscommon and Galway, where they were seated from
ancient times.
A massive amount of Ireland's native population left the island in the 19th
century for North America and Australia in hopes of finding more opportunities
and an escape from discrimination and oppression. A great portion of these
migrants arrived on the eastern shores of the North American continent. Although
they were generally poor and destitute, and, therefore, again discriminated
against, these Irish people were heartily welcomed for the hard labor involved
in the construction of railroads, canals, roadways, and buildings. Many others
were put to work in the newly established factories or agricultural projects
that were so essential to the development of what would become two of the
wealthiest nations in the world. The Great Potato Famine during the late 1840s
initiated the largest wave of Iris immigration. Early North American immigration
and passenger lists have revealed a number of people bearing the name
MacGeraghty or a variant listed above: Robert Gerity who arrived in
Philadelphia, Pennsylvania in 1858; Patrick Gerrity, also Peter and Phillip, all
arrived in the 1860's; Sally McGarty arrived in New York State in 1847.