Above you see the moment where Francis I was presented for his cousin king Louis XII. The reason this meeting was very important was that Louis XII did not have any male heirs and therefore his cousin was the heir presumptive that means that he was the closest male that could make assumptions to the throne. The reason that king Louis XII had no male heirs was partly sabotage and partly bad luck.
Louis XII was forced by his uncle king Louis XI to marry his handicapped and supposedly sterile second cousin Joan. His uncle did this specifically because he hoped that his branch would die out and therefor unable to ever hire the throne, but since his own son Charles VIII died without male heirs Louis XII became the king anyway. After succeeding the throne of his cousin Charles VIII, the son of Louis XI, he had his marriage divorced by pope Alexander VI and married his window Anne of Brittany.
Getting a divorce was not easy at that time though not even for a king. In other to get the marriage annulled one needed a good reason. The most common reason to get a marriage annulled was to announce the marriage void because of consanguinity. Even though he had witnesses that said that the two were closely related there was no written proof of this. He couldnt proof either that he married under the legal age of consent which was 14 at the time even though he claimed to have been twelve at the time and others estimated him to be between 11 and 13 again their was no written proof so this was dismissed. What he came up with then was really insulting to Joan and she therefor fought really hard for her case. Louis claimed that Joan was physically malformed (providing in great detail precisely how) and claimed that this had hindered him to consume his marriage with her. She said it was nonsense and that he had been boasting to others that he had mounted her three times a night. Louis claimed that his sexual performance was due to witchcraft and she asked him how he could possibly know what it was like to make love with her if he had never tried. Had the pope been a neutral party she would have actually won the case but the pope ruled in Louis XII favor and ruled that Louis had been forced to marry his cousin by her father. Joan was dismissed and she reluctantly said that she would pray for her former husband and became a nun.
Louis XII really tried to get male heirs with his second wife Anne of Brittany but they were very unlucky. His wife got 3 miscarriages, 4 stillborn sons and 2 healthy daughters. He also got one bastard son but since bastards weren’t allowed to inherit this didn’t help. Louis XII tried to make the best of the situation by betrothing his eldest daughter Claude to his cousin Francis I. That way she would at least be queen over her fathers land.
After the death of Queen Anne Louis XII got remarried the same year with Mary Tudor the sister of Henry VIII. They tried to get a male heir again but the king died 3 months later, exhausted of all the bedroom exertions. Louis XII died 1 januari 1515 after he reportedly got a severe case of gout on december 26 1514. Since there were no male heirs the throne went to Francis I and his wife Louis XII daughter Claude of France.