Complex sentence: At the time of the 1967 takeover, Threlfall's was the 8th largest brewery in the United Kingdom, and the largest in North West England and after the takeover Whitbread, a predominantly southern based business, became the second largest brewery in the United Kingdom.
Split into simpler sentences: At the time of the 1967 takeover, Threlfall's was the 8th largest brewery in the United Kingdom, and the largest in North West England. After the takeover Whitbread, a predominantly southern based business, was the second largest brewery in the United Kingdom.