SecretLeeds - History, culture and architecture in Leeds

As a pirate fan I watched all three series of "Black Sails" on TV. It is written as a form of prequel to "Treasure Island" but many of the names of the characters portrayed actually existed. In series three one of the main characters - Captain Jack Rackham - talks about his youth. He claims to be from Leeds and goes on to say that his father and grandfather were both tailors in the city. Now, I've checked online and whilst some sites agree with the Leeds link, others claim that he hailed from Bristol and even from Jamaica. He was also known as Calico Jack for reasons not made entirely clear. His main claim to fame appears to be his design and introduction of the original "Jolly Roger" black flag: his version shows a skull and crossed cutlasses which later evolved into the more common skull and crossbones.
Can anyone shed any light on a possible Leeds link?
Series 4 is to be aired later this year - with Jack Rackham still in the show's cast.