According to Yuengling's write up:
One of our distinct classic beers brewed since 1829, Yuengling Lord Chesterfield Ale has as much rich heritage as it does flavor and appeal. Crafted in a unique two-stage European brewing style for enhanced bitterness, it utilizes both conventional kettle hopping and dry hopping after fermentation resulting in a dry sharp finish. Brewed with select hops, its distinct robust flavor is derived from a delicate combination of sweet maltiness and lingering herbal bitterness. Lord Chesterfield Ale's bright gold color is complemented by a lightly laced foam head and fragrant zesty aroma. This fine Ale compares with the very best crafty-style beers. It pairs flawlessly with many foods including seafood dishes and fine cheeses.
A nice inexpensive alternative to British beers if I am stuck in the colonies. However, given the dates between Chesterfield's death and when the beer was first brewed, I doubt the Yuengling account for the name is correct. Perhaps it has something to do with Chesterfield's service as the Lord Lieutenant of Ireland.
I have to admit that I like the name given its royalist-monarchistic bent.
There is this fantasy that Sam Adams would have the same connotation as Young's Old Nick in my ideal world: A treasonably good ale. Loyalists viewed Adams as a sinister figure. Peter Oliver, the exiled chief justice of Massachusetts, characterized him as devious Machiavellian with a "cloven Foot". I guess there is some hope as there were negative assessments of Adams in the first half of the 20th century where he was portrayed as a master of propaganda who provoked mob violence to achieve his goals.