The historical context of St. Bernard's life is complex. He was born in 1090 at Fontaines and he died in Clairvaux on August 21, 1153. The three most important events in his life were as follows.
First, St. Bernard lived in a time of the crusades. He was a spiritual father to the knights Templar. The Templars took an oath to defend the Holy Lands. Hence, we are in a world where there is military and religious conflict with Muslims.
Second, St. Bernard lived in a time of powerful religious controversy. He went head to head to Peter Abelard. The chief issue was on the atonement. Abelard argued that Christ died only to show God's love; there was no idea of Christ bearing sin. St. Bernard made the chuch reject Abelard's teaching.
Third, Bernard also lived through religious schism in the Catholic church. He sought to bring reconciliation and he succeeded.