Here's what they say on the UK Butterflies website.
"The Meadow Brown is one of our commonest and most widespread butterflies, and a familiar sight throughout the summer months. This species can be found in all parts of the British Isles, with the exception of the most mountainous regions and Shetland. This is a highly variable species with four named subspecies found in the British Isles, although the differences between them are often subtle.
Maniola jurtina ssp. jurtina
The species was first defined in Linnaeus (1758) as shown here (type locality: Europe, Africa). The nominate subspecies has not been recorded in the British Isles.
Maniola jurtina ssp. insularis
This subspecies was first defined in Thomson (1969) as shown here and as shown in this plate (type locality: Isle of Wight, England). This subspecies is found throughout England, Wales and Scotland south east of a line between Ayrshire in the south west and Moray in the north east."
You see, at Mottisfont they were leaving several large fields to grow wild, so the butterflies, bugs, bees, etc, all had somewhere to play.
There are so many different varieties of butterflies in England, that a girl from the colonies can get somewhat excited and overwhelmed at which to photograph first.
That day, I really took to the little Meadow Browns. They were delightful and they were everywhere.