Generally speaking, a good credit history and score is very important because it will dictate the terms and interest your able to lock down and save you, potentially, a lot of money.
Since 2008, the banks and mortgage companies have really stiffened their criteria for lending so you will need a minimum score of, at least, 620-650 to get financing.
Most importantly, though, is that you shop around. Different lenders will have different rates and criteria so no matter how high or low your score, make sure you find the best terms for you and your goals. Hope this helps.