Preheat oven to 350°F. Grease or line a 9"x5" loaf pan with parchment paper.
First, make the vegan buttermilk by adding the apple cider vinegar to the non-dairy milk and letting it sit for 5 minutes.
In a small bowl, whisk together the flour, baking soda, and cinnamon. Set aside.
In a large bowl, whisk together the flax eggs, mashed figs, rum, sugar, and vegetable oil. With a spatula or wooden spoon, mix in the dry ingredients and vegan buttermilk until combined.
Transfer the batter into the prepared loaf pan. Bake for 45-50 minutes, until toothpick inserted into center of the loaf comes out clean. Let it cool completely before slicing and serving.