When did Daniel Lissing (Jack Thornton) leave When Calls The Heart?

When Calls the Heart fans were stunned when Jack Thornton met a sudden end on the show! When did it happen and why did Daniel Lissing leave the series?

Related Keywords

,Jack Thornton ,Daniel Lissing ,Elizabeth Thatcher Erin ,Jack Thornton Daniel Lissing ,Elizabeth Thatcher ,Erin Krakow ,Coal Valley ,Mountie Jack Thornton ,Australian Born Lissing ,Cleaning Lady ,Christmas Star ,Entertainment Tonight ,Tv ,