Complex sentence: Lawrence chose to stay at the more prestigious Yale, but found that the appointment without having first been an instructor was resented by some of his fellow faculty, and did not necessarily lift his social status among people who were unimpressed by his South Dakota immigrant background.
Split into simpler sentences: Lawrence chose to stay at the more prestigious Yale, but found that the appointment without having first been an instructor was resented by some of his fellow faculty. He also found that his appointment did not necessarily lift his social status among people who were unimpressed by his South Dakota immigrant background.