Well, to be honest, my LEGO setting would be more POST-Post-apocalyptic, and the agent of the apocalypse was a massive Anti-matter war that wiped out close to half the earth's population, but left no radiation behind, although it did cause some rifts in the space-time continuum to open up, which is one of the reasons why you have characters from all different settings... of course, such portals happened from time to time BEFORE the Final War, so it's basically a massive-multiplayer crossover setting. It helps if you realize that this setting is based on the LEGO wars my brother and I fought (we were on the same side against common enemies), and thus is a parallel universe that split off our own sometime around 1989 when George Bush (Sr.) usurped power, declared himself king and teamed up with the Sheriff of Nottingham and Guy of Gisborne so he could tax all the poor people to death, but Pennsylvania, under the leadership of Yours Truly, my brother and Robin Hood and his Merry Men successfully revolted.
What followed was wars against Sauron, who had somehow reawakened from his ancient defeat, The Galactic Empire (initially I was using a modified USS Enterprise from Star Trek against them, but later started adding X-wings and such to the fleet), and Pirates (although that one ended when said pirates, including Capt Hook, Capt Long John Silver and Capt One-eyed Willy, decided to accept an offer to form a navy for the recently liberated US in exchange for pardons), and finally the mad scientist, Dr. Regis Blackguard sometime in the mid 2000's.... When he realized he was going to lose, he had his best hackers hack into the controls for everyone's long-range antimatter missiles and launch them all, which was known as the Final War. (a.k.a. my first LEGO dark age), and everyone has been rebuilding since then....
Balin isn't the only LoTR refrenece: Gandalf is the FRA Army Joint Chief of Staff, and Gimli Gloinson is a sergeant in the Army Rangers, along with Cpl. Ugluk Uruk-hai (he found religion)... Not to mention that Galadriel is a Federal Senator, and Legolas is leader of the Elven Ranger Corps (basically a militia unit). Other crossover characters are: Admiral James Hook, Chief of Naval Operations, General Clare, Commandant of the Marine Corps, General Gordon Freeman, Air Force Chief of Staff, Lt. Felix Jaeger & Sgt. Gotreck Gurnisson of the SOCOM "Men at Arms" division, PFC Snorri Nosebiter of the Army Rangers, Col. Henry "Indiana" Jones of the Army Rangers, etc.
Granted, some of the shout-outs are rather obscure, but that's half the fun.