<Tr> <Td_colspan="2"> Website </Td> </Tr> <P> When Calls the Heart is a Canadian - American television drama series, inspired by Janette Oke's book of the same name from her Canadian West series, and developed by Michael Landon Jr . The series began airing on the Hallmark Channel in the United States on January 11, 2014, and on April 16, 2014 on Super Channel in Canada . </P> <P> The series originally debuted as a two - hour television movie pilot in October 2013, starring Maggie Grace as young teacher Elizabeth Thatcher and Stephen Amell as North West Mounted Police officer Wynn Delaney . In the television series Erin Krakow is cast as her niece, whose name is also Elizabeth Thatcher (played by Poppy Drayton in the movie), and Daniel Lissing plays a Mountie named Jack Thornton, with Lori Loughlin reprising her role as coal mine widow Abigail Stanton . </P> <P> On April 24, 2017, Krakow announced via the Hallmark Channel website that the show would return for a fifth season, which premiered with a two - hour Christmas special broadcast as part of Hallmark's Countdown to Christmas event and resumed in February 2018, ending in April . On March 21, 2018, Hallmark renewed the series for a sixth season . </P>

Why did the actors change in when calls the heart
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