irregardless, 1876 (OED: 1912)

[Geoffrey Nunberg]

 From Google Books:

"As far as my knowledge extends among the intelligent colored people
they do not desire their children and the white children to go to
school togehter. They want schools and are willing for the whites to
have schools, and the democratic party is in favor of educating the
children irregardless of race, color, or previous condition."
Testimony of J. G. Taylor, resident of Onachita Parish, La., Dec. 18,
1876, in Report of the Sub-Committee of the Committee on Privileges
and Elections of the United States Senate, Vol. 1, 187, p. 476. The
speaker repeats the word in the following paragraph so this is likely
not a typo.

The OED's first cite is from Wentworth's 1912 American Dialect
Dictionary, which puts the word in western Indiana; this quote
suggests an earlier Southern origin.

Geoff Nunberg

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