With Lady Salisbury, afterwards Lady Derby, he kept up for more than thirty years a correspondence which only ended with his death.

It was Froude who introduced Lady Salisbury to Carlyle, and she thoroughly appreciated the genius of both.

Her intimate knowledge of politics was completed when Lord Derby sat in Disraeli's Cabinet.

But she was always behind the scenes, and it was from her that Froude obtained most of his political information.

Their earliest communications, however, referred to the Elizabethan part of the History, especially to the career and influence of William Cecil, Lord Burghley.