His parents were born in Pennsylvania.
He married to Barbara Bair.
They appear in the 1850 thru 1880 census of Prairie Township, Holmes County, Ohio.
John was reared as a farmer, a vocation which he followed throughout his life. He lived on a farm adjacent to his father, Peter, in Holmes County, Ohio. In national affairs he was very zealous, taking an active interest in operating the Underground Railroad that ran through several routes in Holmes County north to Canada. Previous to the Civil War he was an ardent Anti-slavery man and an active conductor in the service of the Underground Railroad, and his son (Peter Calvin) still remembered having seen many strange black men and boys hiding in their neighborhood on their way to Canada and freedom. One of the stations of this Underground Railroad is visible to this day near Salt Creek on State Route 83. It was a rocky cavern concealed by brush that often sheltered twelve to fifteen Negroes during daylight, having been brought there by some friendly person the night before. Mr. Croco would feed and care for them through the day and then drive them north at night to the next station. The zeal of Mr. Croco and his brother Keifer caused them to have numerous enemies. They were even shot at. The slavery sympathizers, learning of John's activities in this direction, threatened him with death and finally, after he had evaded several mobs, he was captured, over-powered and his skull crushed. Four surgeons said his wound was fatal but he was a very powerful man with a wonderful constitution and physique. Surgeons covered his brain with a gold plate and gave him little chance of survival, but his healthy constitution and physique made for a full recovery. He continued in his friendliness to Negroes.
He sent a substitute to the Union army during the Civil War.
John answered the call from the west and moved to Kansas.
In 1880 they moved to Winfield, Cowley Co., KS and then to Sterling, Rice Co., KS.
In 1900, John and Barbara were living with their daughter, Martha McClure, in Sterling City, Rice County, Kansas.

Children of John and Barbara:
Martha Croco McClure (ca.1843-unk)
Hannah Croco (ca.1845-unk)
Mary Croco (ca.1847-unk)
Barbara Ellen Croco (1849-unk)
Melancthon James Croco (ca.1851-1886)
Peter C. Croco (1853-1925)
Sarah Croco (ca.1855-unk)
Susan Croco (ca.1857-unk)
Emma B. Croco (ca.1861-unk)