My reference doesn't have a lot of information, but I will try to seek out more I can find it.
The 1265th Engineer Combat Battalion was activated 27 Mar 44, atCamp Van Dorn, Miss.; (there was another inquiry/response related to Van Dorn recently) departed Canal Zone, 15 Nov 44; arrived England, 27 Nov 44; arrived France-ETO, 18 Mar 45.
Rhineland, 15 Sep 45 / 18 Mar 45 Central Europe, 22 Mar 45 / 11 May 45.
The unit was non-divisional, which means that it's documented history will be difficult to generate, but I'll try.
Meanwhile, I hope that this little bit is helpful.