Charles Lwanga was a servant at the royal court in what is now Uganda. In 1884 a new king, Mwanga, came to the throne. He saw Christians as foreigners trying to take over his country, and he began persecuting the Christians who were on his staff. On May 26 1886 sixteen Catholics and ten Anglicans were sentenced to death for refusing to deny their Faith, and a week later they were all martyred by being burnt alive.
I found an article about St Charles Lwanga and his companions that was written by Fr Jimmy Lutwama AJ, the Parish Priest of St Mary and St Benedict in Coventry, England. Father Jimmy comes from Uganda, so I thought you might like to hear what he had to say. He wrote it last year.