This impressive, detailed cathedral is one of the city's most essential sights, in part because it looks so different from other churches and cathedrals in Lodz. With an octaganal plan and ornate domed roof, it looks much more Russian than Polish -- and there's a reason for that. 
The cathedral was built between 1880 and 1884 by a committee of Lodz's largest industrialists, whose names you'll find throughout this guide (including Karol Schreiber, Julisz Heinzel, Edward Herbst, and Izrael Poznański), and it was largely a show of loyalty to the Russian Tsars who controlled the area that is now central Poland at the time. Though none of the industrialists were orthodox themselves, they likely thought that building a Russian-Byzantine-style Orthodox cathedral would gain them favor and thus, further financing for their projects. Together, members of the committee put forth the 69,000 rubles (around 800 Euro today) for its construction, and the building was designed by one of the city's top architects, Hilary Majewski.

The design was pretty typical of those famous Russian orthodox cathedrals, with one tower topped with an onion dome, the central part with its own, shallow domed roof, and facades decorated with rows of arcades. Inside, there were stained glass windows, bells, frescoes, and an impressive three-row oak iconostasis.

Amazingly, the cathedral made it through the first world war without destruction and even remained operational, despite many of the Russian orthodox residents leaving the city. When Poland became a country again, after years of partitions, the cathedral was made into the seat of a parish serving community members from neighborhoods and towns around the city. 

During WWII, the Orthodox clergy issued false certificates of baptism to Jews from Lodz, and then hid their church bells from the Nazis who demanded they be melted down. The church continued operations throughout the 20th century and underwent an extensive renovation in the 21st, though it kept its original exterior. 

Certainly an impressive piece of pre-war history, and truly a sight to behold, this cathedral is a must-visit.