I'm not sure how the history of tanks went but Hungary could have one right before WWI. The designer basically covered a Holt-Caterpillar tractor with steel plates and put a machine gun above in a turret. The second version got a flamethrower instead and was more box like. This was in 1912/13. During a military exercise - as the story goes - the tank approached His Majesty, the Kaiser und König - two in one - but his horse got scared so he judged: enough of this silliness, the K.u.K. Armee doesn't need such reckless faggotry. Next thing we know the Serbs kicking our buttocks. Great job, Your Majesty!
Depending on who tells you the story the victim of the shortsightedness of the Emperor can be an armored car of the same military inventor.