The settlement of Aleksandrów was founded in the 19th century (ca. 1816 r.) by the owner of local estates, Rafał Bratoszewski, Sulima coat of arms, who desired to make it a centre of the textile industry. He succeeded in creating favourable conditions, especially for weavers who came from Prussia to take up residence in Aleksandrów. The settlement initially attracted mostly colonists from Greater Poland and Silesia. Aleksandrów was named in honour of Tsar Alexander I, thanks to which it could obtain municipal rights in 1822. After the death of Bratoszewski in 1824, the town became the property of the Kossowski family, Dołęga coat of arms. Its growth came to a halt soon thereafter in the face of competition from the neighbouring textile centres: Łódź, Zgierz and Pabianice. 1832 was marked by economic recession. It was only in the late 19th and early 20th century that Aleksandrów recovered with the mushrooming of knitting plants, e.g. in 1888, Juliusz Paschke, a German factory owner, set up the first mechanical stocking factory. Other factories were established by Gustaw Paschke, Rudolf Schultz, Adolf Greilich, Karol Pfeiffer, Gothilf Knappe, Gustaw Hirsch, Karol Steckl and Albert Stiller. They produced large quantities of socks, stockings and sweaters. Consequently, Aleksandrów came to be considered the cradle of the Polish stocking industry, which holds a dominant a place in the town's economy also nowadays. Aleksandrów is even sometimes called by its inhabitants a "sock-town" (Skarpetkowo in Polish).
During the January Uprising, in 1864, the town was taken over by Polish insurgents. After the defeat of the uprising, in 1869, the tsarist authorities deprived Aleksandrów of its municipal rights. During the First World War, in the end of 1914, the town was bombarded and invaded by the German troops. After Poland had regained independence, Aleksandrów reclaimed its municipal rights in 1924. During the first census carried out in 1921, there were 8,236 inhabitants in the town, including 37% Germans, 34% Poles and 29% Jews.
Following the Second World War, Aleksandrów lost forever its character of a city where three nations and ethnic groups coexisted. After the town was taken over by the Germans in 1939, it was incorporated into the Third Reich as part of so-called Reichsgau Wartheland. A time of oppression began. The synagogue was burnt and demolished, the monuments of Kościuszko and Piłsudski were destroyed and the Catholic church was turned into a warehouse. All streets and squares were given German names. Jews and Poles had to comply with discriminating laws and work for the aggressor. The Germans started to organise round-ups, executions and resettlements. The whole Jewish population was deported in December 1939 and later killed. In 1945, the town was invaded by the Soviet Army. Almost all German inhabitants of Aleksandrów were displaced in the period from 1945 to 1948. The Communist authorities and police resorted to various repressions and abuse of power.
From 1975 to 1998, Aleksandrów was administrative part of the former Łódź Province. After the transformations of 1990, various new investment projects were implemented in the town: the renovation of the butcher's stalls, construction of a sewage treatment plant and an indoor swimming pool, extension of the Sports School Complex and its sports field, construction of a sports hall and an Orlik sports field at Primary School No. 4, construction of a cycle path, as well as the widening and replacement of the road surface to Łódź and reconstruction of the town park. The reconstruction of the marketplace and renovation of the Evangelic church are underway.