Three years later, he learned that La Salle was returning to ascend the Mississippi, from the Gulf of Mexico, and proceeded south on his own to try to meet La Salle on his ascent.
La Salle was returning to ascend the Mississippi. This was from the Gulf of Mexico. He learned this. This was three years later. He proceeded south on his own to try to meet La Salle on his ascent. This was three years later.