Born at the Roost to Bolland Terrick and Tressa Terrick nee Arryn, Lothar was the final child of the two. A few years after his birth his family left the Roost for the Vale where he spent his childhood as the youngest son of Bolland 'the Crimson Axe' Terrick, Master at Arms for House Arryn and favored son of Lord Tomas Terrick but having the misfortune of being born 18 months after his brother Jerold.
His early years he was doted on by his mother who taught him what it was to be a proper nobleman, dancing, drawing, law and calligraphy. These were some of the most enjoyable years for Lothar as his only worries were what book he would read next, or what he would capture in his sketch book. This continued until his 12th nameday when his father saw him sitting under a tree drawing a butterfly on a flower and realized that his youngest son wasn't a fraction of the man that a Terrick should be and took him under his wing to make a man out of him.
This was when Lothar's easy going and enjoyable life went away and the more martial and physical education from the Crimson Axe began. Daily he worked in the training yards under the exacting and very shall we say firm hand of his father. He began learning all the knightly weapons like his brothers had to before him, axes, maces, swords and spear, how to ride and how to properly use the lance not for tourneys but for war. He was trained next to squires from the Vale houses and began to idolize the Knights of the Vale, and the romantic ideals in his head from the books he'd read as a carefree child.
Around his 14th nameday his father handed him off to Ser Rolstad Hunter from House Hunter of Longbow Hall as a squire with the final goal of making a man out of him. So for three years Lothar learned to hone his skills with the knightly weapons (axe, spear, sword, mace). His natural talent with the bow was discovered during his time as a squire when he was handed a bow just to teach him the basics for defense of a castle and he outdid all the other squires at Longbow Hall, in fact he was shooting better than some of the current men at arms without any training, so for the next few years hunting and archery was also added to his plate to try and fine tune his natural talent with archery but at the same time not ignore his training as a squire. After three years of training with Ser Rolstad he received word from his father requiring him to return home and attend his family, not willing to risk the ire of the Crimson Axe Lothar returned to his family and departed the Vale for the Riverlands and the Roost once again.