So it was a few pages back, but I've recently loaded up the file where Istarted as a loyal Mercian vassal but after my liege was usurped I went out and took the throne of Essex for myself. Through marriages and other less friendly means I gained claims on the southern English territories and expanded. I formed the English kingdom while Wales, the Mercian remnants, and Northumbria punched one another in the nads.
I took Mercian territory while they dealt with Wales and a large (for them) rebellion. After they were split between us I offered Northumbria vassalage and they actually accepted. I'm allied with the newly renamed Scots and after a series of duels and assassinations have seriously crippled Wales' ruling family.
In the latest war with Wales I managed to capture all of their cowardly hiding King's family, including his wife, and executed them all. Soon they will be pushed back to their historical border and the British Isles will be historically accurate border-wise.
I used to hold Blois through marriage but gave it up when france declared war for it. I gave it up immediately, it was definitely not worth the fight. I want to focus on Scotland and Ireland before setting my sights elsewhere.
In other news, Italy controls about 80% of the Iberian peninsula, the Norse are spread deep into the continental mainland but are anything but unified. It's around 1100 by the way. France is still three separate kingdoms though they are each pretty strong.
Oh also I think I forgot to mention using the rebels and warmongers mod. On a phone, so it's not an easy check.