Henry the Lion was one of the most influential rulers of the HRE in the high middle ages. He was duke of Saxony and Bavaria. However, all his efforts of centralizing his rule over Saxony trying to make it more like England of his father in law made him quite a few enemies and he was bailed out lots of times by Frederick. So when he didn't heed Fredericks call for help and wanted Goslar back (which he got in 1154 and lost in 1169), he sealed his fate by biting the one hand that protected him from his enemies leading to the Balkanization of Saxony. But what if it had come differently?
The Saxon war in 1167-1170 was a direct response of North German princes against the expansionism and centralizing efforts of Henry the Lion. The coalition consisted of the Archbishop of Magdeburg, the Archbishop of Cologne, the bishop of Hildesheim, Louis of Thuringia, Albert the Bear and his sons, Otto of Meissen, the dukes of Assel, Christian of Oldenburg. Only Pribislaw of Mecklenburg and the duke of Schwerin supported Henry as both of them were invested by him. Despite being battered heavily Henry came out of this relatively unscathed thanks to Frederick protecting him. But what if Henry was more successful and broke the coalition for instance by killing and/or capturing Albert the Bear and his sons? This loss wouldn't wipe out the Ascanians as Albert did make quite a few sons but it would seriously weaken teir position. Could Henry make the remaining Ascanians give up Brandenburg which was still in its infancy at this point and give them Bavaria his claims to instead? IOTL Henry focused on Saxony because he had few territories in Bavaria and the opportunities for expansion were far greater since he split off the Austrian part thus denying eastward expansion. Given that Frederick let Henry get off scott free despite strong protests of the coalition that beat Henry, I'd stay chances are Frederick would support a victorious Henry too. The fact that Frederick also married Henry to Matilda of England further proves their close alliance.
Lets best to look at why Henry fell from grace in the first place and what led to it. Henry had ambitions of centralizing/unifying Saxony under his rule and making the Duke of Saxony as a step between the Saxon princes and the Emperor. He did so by acquiring land and stripping the nobility and the clergy of rights and privileges. By doing this he made himself a lot of enemies both within Saxony and outside. Frederick Barbarossa was the protector of Henry even when Henry lost against the coalition of north German princes. Once Henrys uncle Welf IV as well as his sons died of dyphteria in the Italian campaign in 1167, Frederick Barbarossa inherited among many other estates the estates of Henrys uncle. Henry had a inheritance treaty with his uncle but refused to pay, which Frederick gladly replaced him. As a condition to aid Barbarossa, Henry wanted Goslar probably because he wanted to use its rich silver mines to pay for his centralizing efforts. However, with Henry the Lion having won the Saxon war, he would have destroyed his opponents and likely even gain a lot of land (maybe even Brandenburg). Henry would not have a reason to not come to Frederick Barbarossas aid. His enemies the Archbishops of Cologne and Magdeburg would not be able to seize the opportunity and cozy themselves up to Frederick.
the Duchy of Saxony (yellow) and Henrys allodial land (orange)
The Saxon war in 1167-1170 was a direct response of North German princes against the expansionism and centralizing efforts of Henry the Lion. The coalition consisted of the Archbishop of Magdeburg, the Archbishop of Cologne, the bishop of Hildesheim, Louis of Thuringia, Albert the Bear and his sons, Otto of Meissen, the dukes of Assel, Christian of Oldenburg. Only Pribislaw of Mecklenburg and the duke of Schwerin supported Henry as both of them were invested by him. Despite being battered heavily Henry came out of this relatively unscathed thanks to Frederick protecting him. But what if Henry was more successful and broke the coalition for instance by killing and/or capturing Albert the Bear and his sons? This loss wouldn't wipe out the Ascanians as Albert did make quite a few sons but it would seriously weaken teir position. Could Henry make the remaining Ascanians give up Brandenburg which was still in its infancy at this point and give them Bavaria his claims to instead? IOTL Henry focused on Saxony because he had few territories in Bavaria and the opportunities for expansion were far greater since he split off the Austrian part thus denying eastward expansion. Given that Frederick let Henry get off scott free despite strong protests of the coalition that beat Henry, I'd stay chances are Frederick would support a victorious Henry too. The fact that Frederick also married Henry to Matilda of England further proves their close alliance.
Lets best to look at why Henry fell from grace in the first place and what led to it. Henry had ambitions of centralizing/unifying Saxony under his rule and making the Duke of Saxony as a step between the Saxon princes and the Emperor. He did so by acquiring land and stripping the nobility and the clergy of rights and privileges. By doing this he made himself a lot of enemies both within Saxony and outside. Frederick Barbarossa was the protector of Henry even when Henry lost against the coalition of north German princes. Once Henrys uncle Welf IV as well as his sons died of dyphteria in the Italian campaign in 1167, Frederick Barbarossa inherited among many other estates the estates of Henrys uncle. Henry had a inheritance treaty with his uncle but refused to pay, which Frederick gladly replaced him. As a condition to aid Barbarossa, Henry wanted Goslar probably because he wanted to use its rich silver mines to pay for his centralizing efforts. However, with Henry the Lion having won the Saxon war, he would have destroyed his opponents and likely even gain a lot of land (maybe even Brandenburg). Henry would not have a reason to not come to Frederick Barbarossas aid. His enemies the Archbishops of Cologne and Magdeburg would not be able to seize the opportunity and cozy themselves up to Frederick.
the Duchy of Saxony (yellow) and Henrys allodial land (orange)