Your maternal line stems from a branch of H called H1. The common ancestor of haplogroup H1 likely lived between 9,000 and 15,000 years ago, not long after the end of the Ice Age. Her maternal-line ancestors had been among the former inhabitants of continental Europe, people who were pushed out of the north by glacial ice sheets during the last great peak of the cold at the end of the Ice Age. They sheltered for thousands of years in warmer refuges along the Mediterranean, including in the Iberian peninsula. H1's common ancestor likely lived within that Iberian refuge, and as the Ice Age faded away her descendants migrated northwards.
Following the Atlantic coast, they carried H1 into what would become the British Isles. As the climate continued to warm, some carried the haplogroup as far north as Scandinavia, while others went east. Still others turned southward, crossing the Strait of Gibraltar into northern Africa. Today, about 13% of present-day Europeans trace their maternal ancestry to the H1 haplogroup, and for the Spanish population that rate is nearly 25%. It also reaches significant levels outside Europe, from Morocco and Tunisia to Lebanon and east into Central Asia.