How did the British government come to control Iranian oil in the early 1900’s?

Hey! I’m aware that the British government controlled a significant share of Iranian oil through their Anglo-Persian Oil Company in the 1900s, but I’m wondering how this state of affairs came to be? Did the Persian government cede their rights to this oil? Were manipulative or dishonest tactics used to force the Iranians?

I’m also interested in a brief analysis of the impact of this oil deal on today given the modern politics.