Kate Steele was born in Baltimore, Maryland on 14 December 1861. She was the daughter of lawyer Isaac Nevett Steele and the former Rosa Londonia Nelson, both Maryland natives. She was one of eight known children in the family.

Kate never married and lived in Baltimore with her unmarried elder sister Rosa and by 1910 both were residents of North Charles Street in that city. 

Miss Steele was aboard the Carpathia as a first-class passenger when that ship rescued the survivors of the Titanic disaster; she was travelling with the Miss Fowlers (Amelia, Meta and Alice). Deciding to continue on their planned vacation after depositing the survivors in New York, Miss Steele said:

“We are glad, we four, to express our absolute faith in our fine captain by sailing with him again for our original destination. We are glad to sow how safe we feel in his hands.” — The Baltimore Sun, 20 April 1912

Miss Steele eventually returned to Baltimore from where she continued to travel whilst living with her sister. She died on 3 October 1944 and was buried in Greenmount Cemetery, Baltimore.