In the last few years, a site of a hitherto unknown battle of an imperial roman army against some germanic tribesman in (c.) 235 AD at the Harzhorn has been dug up by german archaeologists.
http://en.wikipedia.org/wiki/Battle_at_the_Harzhorn
Historians regarded the ancient reports that the roman troops under Emperor Maximinus Thrax ventured so deep into germanic territory at that time as exaggerated, by a factor of ten. The reports stated something like 300 to 400 roman miles, but historians just deleted a zero - wrongly, as is shown now.
What makes this site special is that there are enough remains of weapons, especially projectiles, and other items that it is possible at least partially to recreate what happened there - from where the romans came (even further north, probably from as far as the Elbe river), where the roman troops stood (especially their scorpios), what kind of troops the romans had (syrian archers, cavalry, standard infantry), to which positions archers and scorpios fired, which legion was involved (Legio IIII Flavia Severiana Alexandriana, from Belgrade).
I think this is quite an exciting history - an emperor that is not very well known today leads an army deep into enemy territory as a retaliation for earlier attacks, fights at least one battle and returns from this, and the battle is all but unknown until some hobby archaeologists stumble (illegally) upon some remains of that battle.
The Varus battle in 9 AD is much better known - three whole legions were eradicated by germanic tribesman. Standard lore was it that roman operations within germania magna all but ended with that battle. Now, this is proven wrong.
Dot..
The is very interesting. Just proves how little we actualy know about the past sometimes.
Several comparable discoveries have been made in Egypt, which have either overturned "established" dogma or opened up entire new chapters. The one which particularly stands out for me is the series of excavations at the Retenu/Hyksos capital of Avaris, which suggests that the native people of Kemet (Egypt) had help from the Minoans in retaking their kingdom, probably as the result of a royal marriage and extensive trade agreements. This was unknown until about 15 years ago.