Mail won't import my entire hotmail inbox

I've just upgraded from MacBook mid 2009 to MBP late 2013 and have gotten round to setting up Mail.

I have a few different accounts, but both my Hotmail accounts, when set up on the Mail application only import the last 50 messages or so from my account.

Is there a way to get them to import my entire Mailbox? I have a tonne of usefuls emails (passwords etc) stored amidst them :/

Thanks in advance!