Samuel Alexander Bill MBE (10 December 1864 – 24 January 1942) was an Irish Christian missionary, explorer and the founder of the Qua Iboe Mission (later renamed Mission Africa).Bill was raised in Ballymacarrett Presbyterian Church, east Belfast, but was most notably associated with Island Street Belfast City Mission Hall. His interest in missionary work was sparked by a visit to Belfast by Dwight L. Moody and Ira D. Sankey in 1874. He attended the Harley Missionary Training College in London, then under the leadership of Henry Grattan Guinness; and travelled to Nigeria to commence a work amongst the in 1887. The mission base was founded on the banks of the Qua Iboe River, and this base gave the name to the independent interdenominational mission that Bill founded.