OK, submitted 
I'm in good mood even though I retired, because throughout most of the game I did reaaly well
Retired in 1830 when I lost chance for any victory condition.
Till late game I was a tech leader / 2nd techer (i can't believe it! on imortal! with Shaka!), winning liberalism race and taking replaceble parts.
I founded cionfucianism, but didn't take advantage of it after building a shrine
My problems begun when Ottoman decided to declare war on me, coming with curassiers against my longbows and just a few muskeets. He took quickly 3 of my cities, but in couple of turns, when I got rifles and invited China to my side, I pushed Ottomans back, ending war with 2 former turkish cities (I had to give him astronomy and world map for peace, his cuirasiers - circa 20-30 - were on their way back from china land)
So let's say first Ottoman-Zulu war I won...
Later - Mehmed together with Boudica turned score leader - China - from over 20city empire into 10city vassal of Mehmed. So one of my friends was out of service
2nd Otto-Zulu war was in early 1800 when Mehmed came again with his stack of about 30 cavalries and 20 rifles. At this moment I had only 20-25 infantry counting all my empire. I tried to defend, but Mehmed took my 2 desert cities and was heading towards my main production tiles.
It was obvious I will not defend myself anymore, and will lose at least one of this cities before peace. Mehmed hated me so much, that the peace would last only for ten turns.
Diplo victory - impossible (good relations only with Churchill and Maya)
Spaceship - I lost tech lead to Maya and England because of the war
Religion - Otto/ Boudica,
Conquest/ Domi - not a chance against Mehmed or Boudica
Culture - not a single cathedral in my cities
So the only option was to retire

I'm in good mood even though I retired, because throughout most of the game I did reaaly well
Retired in 1830 when I lost chance for any victory condition.
Till late game I was a tech leader / 2nd techer (i can't believe it! on imortal! with Shaka!), winning liberalism race and taking replaceble parts.
I founded cionfucianism, but didn't take advantage of it after building a shrine

My problems begun when Ottoman decided to declare war on me, coming with curassiers against my longbows and just a few muskeets. He took quickly 3 of my cities, but in couple of turns, when I got rifles and invited China to my side, I pushed Ottomans back, ending war with 2 former turkish cities (I had to give him astronomy and world map for peace, his cuirasiers - circa 20-30 - were on their way back from china land)
So let's say first Ottoman-Zulu war I won...
Later - Mehmed together with Boudica turned score leader - China - from over 20city empire into 10city vassal of Mehmed. So one of my friends was out of service

2nd Otto-Zulu war was in early 1800 when Mehmed came again with his stack of about 30 cavalries and 20 rifles. At this moment I had only 20-25 infantry counting all my empire. I tried to defend, but Mehmed took my 2 desert cities and was heading towards my main production tiles.
It was obvious I will not defend myself anymore, and will lose at least one of this cities before peace. Mehmed hated me so much, that the peace would last only for ten turns.
Diplo victory - impossible (good relations only with Churchill and Maya)
Spaceship - I lost tech lead to Maya and England because of the war
Religion - Otto/ Boudica,
Conquest/ Domi - not a chance against Mehmed or Boudica
Culture - not a single cathedral in my cities
So the only option was to retire