Nice! Although I personally found it expedient to crush Ethiopia in order to prevent them snowballing. Perhaps focusing on conquering territory in west Africa rather than throwing all your weight at Ethiopia let you capture enough cities to make up the gpt difference.

Congratulations on your impressive victory and the achievement, and good luck going for that final achievement!

There was no need to eliminate Ethiopia; the key was to control the level of aggression effectively. Throughout the game, I maintained alliances with Egypt, Morocco, and Ethiopia, engaging in gold trades for all their GPT, which peaked at around 4,200. After conquering West Africa, I resold the territory to the weakest but highest-bidding power.