The killings came three weeks after the 1836 Battle of the Alamo and further riled Texans in their war for independence.
Willingham speaks tomorrow as part of the weekend commemoration of the 175th anniversary of the execution of 342 men.
Lovers of history can explore the mysteries and relive the intense emotions through re-enactments, lectures and ceremonies in memory of the March 27, 1836, executions.
A memorial service is Sunday.
Willingham's book "The Edge of Freedom" focuses on Goliad. He says the Alamo represents a romantic tale, while Goliad captures a pragmatic approach in the form of a surrender -- a gambit to achieve peace.