The Long Depression (1873-1896)
The most important event of President Grant's second term in office was the severe financial depression by which it was marked. (Source)The 1873 Panic marked the beginning of the Long Depression which lasted 23 years. Like now, it was a time of extreme excess by the extremely wealthy, the Gilded Age, and a time of high unemployment and outright warfare against working Americans. As in the current depression, the richest of the rich found they could profit from depression by corrupting government.
The Great Depression (1929-1940)
Three or four million heads of households don't turn into tramps and cheats overnight, nor do they lose the habits and standards of a lifetime.... An eighth or a tenth of the earning population does not change its character which has been generations in the molding, or, if such a change actually occurs, we can scarcely charge it up to personal sin. ~ FDR adviser Harry HopkinsThe stock market bubble of the late 1920's burst with great effect when the market crashed in October 1929. As in the current depression, a major cause was the rapid collapse of a debt bubble exacerbated by Republican demands that the burden of recover be carried entirely by the unemployed. The Great Depression was short, only eleven years, because of World War II.
The Third Depression (2000-?)
The years between, the Bush Years, were marked by a frantic attempt to maintain stock prices and employment by engineering a massive debt bubble. The effect is similar to keeping a cancer patient looking healthy by pumping him full of meth.
Choose your starting date, it doesn't matter. We are still years away from the end of this depression.