The main figures involved were Sir Henry Lawrence, who organized the defense of the Residency from the beginning of the siege until he was killed in July; Major General Sir Henry Havelock, who led the first relief attempt but was thwarted by heavy losses; and Sir Colin Campbell, the British commander in chief in India, whose troops killed many rebel soldiers and civilians as they successfully extracted those at the Residency. Campbell also later recaptured Lucknow.
Siege of Lucknow Article