After several failures, including an attempt at Liberty (seemed like there was lots of room) and a meandering attempt at Tradition-Science, this was the successful attempt.
Started with 4-cities before National College, Tradition, Desert Folklore, and tried to stay peaceful for as long as possible, which went quite well. With the bonus on golden ages, and having just won my first diplo victory recently on the 2nd Deity challenge, it made sense to go for diplomatic victory again.
After finishing Tradition, I went into Patronage and finished it before starting on Freedom. I wasn't sure what other policies to open (Commerce, I guess would have made sense) so I just kept picking things in Freedom the rest of the game, even when they were no longer significant.
The wars started based around ideologies, which I was 3rd to, but first (and last) to Freedom. With good city state control, I got Freedom passed as World ideology and my religion as world religion. This was really a diplomatic game all the way, in that I was constantly looking for ways to avoid war, keep others busy, etc.
I had a small, weak army until the freedom policy that gave me 6 Foreign Legions, or whatever they were, which arrived early in my first real war (Ottomans, who took out 2 of my city states). I immediately upgraded the 6 free units, soon after added some great war bombers, and was able to hold off the Ottomans and liberate the 2 CS. I wasn't looking to conquer, just play all the way through with 4-city, peaceful as possible...
But, with Dido conquered (Japan and Otto), and Japan on a peace treaty with Otto, it was finally time for them to DOW me. With the mountains and Samarkand in good shape, this was easy enough to hold off and then I pushed back, crushing the Japanese. While some of the other continent DOWed me, but didn't come over, I essentially went back to playing peacefully and eventually got the Diplomatic victory.
I think I was sloppy with my mid-game science and build orders, and could have been in real trouble if the DiploV hadn't worked out, likely losing the space race.
This was a great map. Looking forward to Deity Challenge #4!
United Nations
Victory!
A look at the home continent