Mayor is right. I'm talking about Constantinople.
The new glory of the old
Byzantium was the new capital of the old Roman empire.
did not fall, unlike it's master
Rome fell, Byzantium did not.
It's defenders, high and cold
made assault a disaster
The Theodosian walls were one of the main reasons Constantinople survived so long.
One metre high, heroes they were
They were on their best on horseback.
From the north warriors of great fame
The Varangian guard, an elite infantry unit hired by the Byzantine, came from Scandinavia.
But by their equals beaten they were
The Turks, too, were fighters on horseback.
And all was changed, even it's name.
Constantinople became Is-tan-poleis, (the city in Turk, IIRC) and then Istanbul.