Upper Saxony
It was particularly to distinguish the lands from 'Lower Saxony', a concept which arose later in popular usage (though never enforced) as a term for the original Saxon lands in north and west Germany (where Low German dialects had spread), in what is now the state of Lower Saxony, as well as the adjacent Westphalian region, Holstein and the western part of today's Saxony-Anhalt north of the Harz range (Eastphalia).
Saxon Wars
The Saxon Wars, also called the Saxon War or Saxon Uprising (not to be confused with the Saxon Rebellion of 1073-75), were the campaigns and insurrections of the thirty-three years from 772, when Charlemagne first entered Saxony with the intent to conquer, to 804, when the last rebellion of disaffected tribesmen was crushed. In all, eighteen campaigns were fought, primarily in what is now northern Germany. They resulted in the incorporation of Saxony into the Frankish realm and their forcible conversion from Germanic paganism to Catholicism.