I can't answer the question for a period as early as 1200, but can answer for the end of the medieval period. In his introduction to his small catechism, Martin Luther claimed "The common people, especially in the villages, have no knowledge whatever of Christian doctrine, and, alas! many pastors are altogether incapable and incompetent to teach [so much so, that one is ashamed to speak of it]. Nevertheless, all maintain that they are Christians, have been baptized and receive the [common] holy Sacraments. Yet they [do not understand and] cannot [even] recite either the Lord's Prayer, or the Creed, or the Ten Commandments; they live like dumb brutes and irrational hogs; and yet, now that the Gospel has come, they have nicely learned to abuse all liberty like experts." So, the early reformers at least believed that the common person had very little knowledge of Jesus' life at the end of the Medieval period.

That said, the reformers had significant bias when talking about the Church, and it's likely that the common person would have known at least the basics about Jesus' life. Both the Lutheran Church and the Catholic Church believed that in the Lord's Supper the "Body and Blood of Christ are substantially and truly present"(Confutation of the Augsburg Confession). Both emphasized the importance of teaching this to anyone receiving the meal. To be able to teach that the body and blood were present in the meal, the Church would have to teach Christ's death and resurrection, so the common person probably would have known that story. The Lutheran's "retained" the practice of private absolution (The Augsburg Confession, Article XI), so the common person must have understood the scriptures enough to know what sin was and confess. Because of that, it's reasonable to assume that the common person had some knowledge of Jesus' life.