John Gregg Nichols (December 29, 1812 – January 22, 1898) was an American businessman, builder, and politician.

[1] Nichols served as the sheriff of Jackson County, Iowa, for two terms in the 1840s.

[1] He made the trip to California in 1849, arriving in San Bernardino on December 31, 1849.

[1] They lived in the first brick house to be built in Los Angeles, California.

On January 22, 1898, Nichols died in Los Angeles, California.