Kate Ingeborg Hansen was born July 5, 1879 in Logan, Kansas to Peter Hansen (1846-?) and Alpha Ama Gray (1858-1957), who were married September 1, 1878 in Phillipsburg, Kansas. In 1896 she graduated from Beloit High School, Beloit, Kansas, and went on to earn her teaching license. Her first teaching position was at a rural school just east of Marvin in Phillips County, Kansas in 1896. The following year, 1896-1897, Kate taught and served as assistant principal of the grade school in Logan. In 1899, Hansen moved to Lawrence, Kansas and began to attend the University of Kansas. After earning a music teacher's certificate in 1901, Kate took a teaching position in the Denver, Colorado public schools where she taught both music and German. Hansen returned to the University of Kansas in 1902, and graduated with a Bachelor of Arts degree in 1905. She was active in religious organizations, particularly the Young Women's Christian Association. In February 1905, she was awarded a Phi Beta Kappa Key. After graduating, she returned to Denver to teach until she qualified as a missionary teacher.

Kate, with her friend and college classmate, Lydia Lindsey, were appointed by the Reformed Church in the United States to teach at a girls' school in Japan. They left the United States in 1907 to travel to Miyagi Girls' School in Sendai, Japan, 200 miles north of Tokyo, the capital city. They were to be connected with this school for 45 years, and were to help it grow from a high school into a fully accredited Liberal Arts College with a Conservatory of Music.

Hansen returned to the University of Kansas in 1912 and received her Bachelor of Music degree in 1913. Back in Japan, she organized a conservatory course in music, and served as dean of that department until her retirement. She was also acting president of Miyagi College for the years 1916-1918, 1925-1926, and 1934-1935. In 1926 she entered the graduate school of the Chicago Musical College and received her Masters of Music with honors in 1927.

In 1941 Hansen and Lindsey returned to the United States on the last boat to reach an American port before the attack on Pearl Harbor. During World War II, Hansen lectured and researched in the U.S. In 1947 she and Lindsey returned to Japan to continue teaching in Miyagi Conservatory. During this post-war period Hansen spent a great deal of time doing relief and reconstruction work. Miyagi College had lost seven buildings in the American bombing of Sendai.

Kate Hansen and Lydia Lindsey were honored in 1951 when the Emperor of Japan conferred on each of them a Citation and the Fourth Order of the Sacred Treasure for outstanding work in women's education. In 1955 the University of Kansas and the University of Kansas Alumni Association honored each of them with the citation of Distinguished Service.

Kate Hansen and Lydia Lindsey returned to Hansen's hometown of Logan, Kansas in 1951, where Hansen died in 1969.