The British government refused her request to nurse in the Crimea

Mary requested to be transferred as an army nurse to the Crimea in a letter to the War Office, where high mortality rates and inadequate healthcare facilities were making headlines. She was turned down, possibly because of her sex or skin tone, though this is not quite apparent.

In October 1853, the Russian Empire and an alliance of the United Kingdom, France, Sardinia, and the Ottoman Empire started the Crimean War. There were allegations of a shortage of supplies and nursing care for soldiers fighting in the war in 1854. Seacole applied to government authorities offering to aid when she was in London at the time to take care of some business, but despite her nursing background, her request was turned down. Seacole blames racial bias for the rejection.