Many ranking of presidents (see the Wikipedia article here) have a stretch of time, from roughly 1850 with Taylor's presidency, to 1880 with Arthur's, where all presidents but Lincoln ranked in the bottom half, and in most cases the bottom quarter, of presidents.
Was there a particular reason this time period in American history produced so many lousy presidents, or was it by sheer bad luck? How much was slavery/the Civil war a driver of these historically poor selections?
The decades following the Civil War can be pretty depressing to study in in detail. If you have a conviction that the government should provide for the common welfare and protect its citizens, the record of failure is pretty bad. More shameful and duplicitous dealings with native Americans, abandonment of freed slaves to the rule of their previous white masters, business trusts setting prices, keeping wages low, and government intervention on their behalf when there are labor disputes.
But it's hard to hang all this on each president. One who came into office with higher ideals would soon find himself buffeted by strong forces who felt otherwise. A good example of one would be Ulysses S Grant, who came into office while the Freedman' Bureau was trying to build civil rights for freed slaves in the South, and intended to have good relations with the Native Nations on the Great Plains. He dropped both, abandoning the freedmen in the face of southern intransigence because the northern voters didn't want to continue to pay for the effort, and abandoning the Native Nations because western voters wanted to have their land. And Grant failed to understand just how easily his subordinates could be corrupted by business interests, and so his administration was rocked by scandals. The tragic thing about Grant is not that he was corrupt or terrible himself, but that he dropped his goals and ideals and became, at the end of his term, a rather dull bureaucrat. But really, there was a limit as to what a President could do against it all: when Chester Arthur vetoed the racist Chinese Exclusion Act, Congress simply overrode his veto. And, if a poll had been taken, likely voters would have agreed with it. And would have agreed to abandon the freedmen, and loot the Native lands. And much of the government was not reformist, either: as the Senate was appointed by state legislatures, in this period, it tended to be filled with political bosses and rich businessmen. like Ohio's Mark Hanna.
This is not to say some Presidents did also not do things to make you cringe. Rutherford B Hayes 's Interior Dept. was a disaster for the Native Nations of the Great Plains, he completely ended Reconstruction, and he and his successors were quite content to send Federal troops to end labor strikes. Yet, there were some incremental reforms that were quite unglamorous but immensely important. The biggest might have been the ending of the Spoils System and the creation of a real professional civil service that was not stocked with only political appointees and ransacked after every election. Garfield, Arthur, Hayes and Cleveland all had a hand in that, and though the Department of Agriculture and the Interstate Commerce Commission may not seem like something you can sing about, they were very important steps in making government less corrupt. Some crimes actually were found out: under Cleveland, there was an investigation into the huge government land grants given to the railroads. In theory, the grants were made in trade for a rail network to be built, but the railroads instead had concentrated on building profitable main lines and sold or speculated with the rest, reaping big profits. Cleveland got around 81 million acres handed back to the government.
So, as people of their time, they were sometimes no better than their colleagues. It seems like they could have done more, And yet, because of them the government in 1900 was in many ways a much better, cleaner, and more useful institution than it had been in 1860.
Scott S Greenberger: The Unexpected President: The Life and Times of Chester A. Arthur