The in-game description of the agreement: "Signing Empires agree to allow their population to migrate to either party's Capital in case of famine".

My understanding: when one of my cities have negative population per turn (produced food is lower than population needs), on the turn they actually decrease, any lost population will move to the other player's capital city.

My questions:
Q1. Is my understanding correct?

Q2. If I am correct, Does that happen automatically among my own cities? why not?

Q3. If I have the agreement with multiple players, what decides which one's capital gets my migrating population?

Q4. If the receiving player's capital is already full of population as well as my capital? will the pop just keep migrating back and forth between those two cities? or just die of starvation if no recipient capitals with enough food available?

Romani0 wrote:

My questions:
Q1. Is my understanding correct?

Q2. If I am correct, Does that happen automatically among my own cities? why not?

Q3. If I have the agreement with multiple players, what decides which one's capital gets my migrating population?

Q4. If the receiving player's capital is already full of population as well as my capital? will the pop just keep migrating back and forth between those two cities? or just die of starvation if no recipient capitals with enough food available?

Sadly, no. It's an effect we would have liked, but it turned out too problematic to implement. Your questions highlight some of the edge cases we'd have to deal with, and as far as I know there were many more. So instead, the "migration" is expressed by a temporary food and industry bonus.

How can this humanitarian aid be triggered? Do all cities have to starve? For me, hunger in one city is not enough. I have signed two such agreements and see no difference when one city (capital) starves. Has anyone seen an effect of this agreement?

I have reported this bug: Bug report

Any update on this bug?

Seems no update.