King Charles III didn’t receive the warmest of welcomes when he arrived in Kenya for a four-day state visit on Monday. Calls are growing for the British monarch to make a heartfelt apology for colonial era abuses as he and Queen Camilla tour the east African country. The tour is the first to a Commonwealth country since he succeeded his late mother, Queen Elizabeth, who died in September after a seven-decade reign. Buckingham Palace announced that King Charles would “acknowledge the more painful aspects of the U.K. and Kenya’s shared history,” which includes the bloody Mau Mau rebellion of the...