-Religious issues
-Tension between King and Parliament
In 1625, Charles I became King of England and Scotland at the age of 25.17 years later, 1642, Civil war broke out in England between Charles I and members of Parliament.
When Charles I became King there was already tension because his father James I had lots of arguments with parliament even suspending them in 1611. When James I next recalled parliament in 1621 it was to discuss the marriage between Charles I and a Spanish Princess but parliament were annoyed because they didn 't want the children to be brought catholic. James I believed in the 'divine rights of kings ' so he did not like to be argued with and the therefore there was a damaged relationship between King and parliament.
Consequently when Charles I became King neither parliament or Charles were happy. Charles who had not expected or prepared to be King had grown up seeing the arguments between his father ad parliament and thought that it was all parliaments fault. Like his father, Charles firmly believed in the divine rights of kings so he found it hard to believe that his father was wrong. Members of Parliament did not want the same thing that James did to happen to them again so they made it harder for Charles to rule without them. With both sides already seeing each other in the wrong there was already increased tension between both sides.
In 1625 Charles I married a French catholic, Henrietta Maria which outraged the MPs because they had not been consulted and because the country was protestant many people disliked the idea of having a catholic for Queen however this was not a main cause for civil war because most people just accepted it but it arose a lot of suspicious in the future that some people argue was the cause of civil war. If he had married a good wholesome English Protestant then his relationship with parliament may not have