What is the main conflict in The Return of Martin Guerre by Natalie Zemon Davis?

"The Return of Martin Guerre" is a reconstruction of the famous case of Martin Guerre's return to the small town of Artigat in Southern France after being absent for eight years or so. However, "Martin" is actually an impostor named Arnaud du Tilh. He is accepted by his wife, family and friends for more than three years, during which time Bertrande becomes pregnant twice. After the so-called Martin Guerre has a dispute over family finances and the sale of some lands that the family owns, he is accused by his uncle and father-in-law Pierre Guerre of being an impostor. There are two trials, the first in the regional city of Rieux. Here Martin/Arnaud is ruled an impostor and condemned to death. "Martin Guerre" appeals the case to the regional Parliament of Toulouse. He is close to being acquitted, when the real Martin Guerre, with a wooden leg, shows up.