Anastasios Stathopoulo started out as a luthier in Turkey towards the end of the 19th century, (but the "founded in 1873" is a myth - Anastasios was 12 in 1873 he may have started his apprenticeship then?), and he emigrated to the USA at the beginning of the 20th Century. By 1909 he had started a luthiery workshop in New York called the House of Stathopoulo making Mandolins and other chordophones. 

When he died in 1915, his eldest son Epaminondas, (or Epi for short), took over managing the business and in 1919 started making Banjos and Banjoleles under the brand name Superb. When the mother died in 1923 he took over full control, phased out the manufacture of Mandolins and Ukuleles, and started to concentrate on high quality Banjos, (with the Recording A being the cheapest and least fancy at $125), this led on to Epi Stathopoulo taking over the Farovan Co. instrument plant in Long Island and incorporating the business under the name Epiphone. 

In 1928 Epiphone started to make Guitars and through the 30's began to increasingly concentrate on them. They also reintroduced Mandolins and the production of Banjos dropped off. WWII put an end to instrument building for a while and Epaminondas died before it ended. The company resumed after the war under the younger brother Orpheus, (who had been Vice President), but things did not go well for Epiphone with important personnel leaving for other companies and in 1957 Gibson brought out the Stathopoulos family and took over the firm. 

I have seen a Japanese made Ukulele branded Epiphone on the sound hole label but I don't know if this was before or after the takeover? Epiphone as a Brand continue still but under the current management its for lower spec far eastern made Gibson style brands and can't really lay much claim to the original heritage, (though it tries too). 

Strand 

I have seen a couple of Banjos from the 1930's branded Strand but I can find nothing about who made them. However in the 1930's Epiphone had a range of intermediate quality Mandolins called Strand - Epiphone did use the same brand name across different instruments in other brands so they are my best bet for the maker. From the catalogues though they were no longer making Banjos at this time and they didn't use the Strand name on Guitars so its only a guess and I would like to find some hard evidence one way or another? I have read an article from 1984 that says Epiphone made Strand Mandolins and Banjos in the 1930's but the article is mainly about Mandolins, (which aren't in doubt), and provides no further evidence for Banjos beyond the opening statement.