[2][3] Walden was born in Rozulas in the Russian Empire (now Stalbe parish, Pārgauja municipality, Latvia) in a large Latvian peasant family.

During this time, Walden started his collaboration with Wilhelm Ostwald (Nobel Prize in Chemistry 1909) which greatly influenced his development as a scientist.

Their first work together was published in 1887 and was devoted to the dependence of the electrical conductivity of aqueous solutions of salts on their molecular weight.

[4][5][6] In 1888, Walden graduated from the university with a degree in chemical engineering and continued working at the Chemistry Department as an assistant to professor C. Bischof.

He also continued his research in the field of physical chemistry, establishing in 1889 that the ionizing power of non-aqueous solvent is directly proportional to the dielectric constant.

During the summer vacations of 1890 and 1891, Walden was visiting Ostwald at the University of Leipzig and in September 1891 defended there a master thesis on the affinity values of certain organic acids.

A year later he defended his doctorate on osmotic phenomena in sedimentary layers and in September 1894 became professor of analytical and physical chemistry at the Riga Technical University.

In his memoirs, he wrote: "My audience usually was crowded and the feedback of sympathetic listeners gave me strength ... my lectures I was giving spontaneously, to bring freshness to the subject ...

[2][4][6][8] After 1915, due to the difficulties caused by the World War I, political unrest in Russia and then October Revolution, Walden had reduced his research activity and focused on teaching and administrative work, taking numerous leading positions in science.

Despite his emigration, Walden retained his popularity in Russia, and in 1927 he was appointed as a foreign member of the Russian Academy of Sciences.

Walden survived on a modest pension arranged by German chemists, giving occasional lectures in Tübingen and writing memoirs.