The Dow Jones Industrial Average finally recovered its September 1929 closing high in 1954.
The Dow reached a pre-crash closing peak of 381.17 on September 3, 1929. After the Wall Street Crash and the deeper economic collapse of the Great Depression, the index fell to a low of 41.22 in July 1932. That represented a decline of nearly 89 percent from the 1929 peak.
Although the market rebounded from its 1932 low, recovery was interrupted by economic weakness and the Second World War. The Dow did not regain its September 1929 closing level until November 23, 1954. This long recovery period illustrates why a market can rise substantially from a trough while still remaining below an earlier record.
The 1954 date refers to the closing high, not the precise intraday high. It is also separate from the later record highs reached during the postwar boom. The crash itself did not single-handedly cause every feature of the Great Depression, but it was a major financial and psychological shock.