Turbine has announced today new Welcome Back Weekend, from December 17th through December 21st. During this period you can play your old characters for free* and get +10% Bonus XP on Mob kills and experience Siege of Mirkwood! Plus, if you come back now you can renew your subscription to LOTRO for only $9.99 per month with any 3-, 6-, or 12-month plan**!
Special Note: You do not need to reactivate your account to participate in the Welcome Back Weekend. Your account will automatically be enabled for the event. If your account does not seem to have been reactivated, please try again in a hour or two. It may take time for our servers to update your status.
You can find more information here