After 1900 the systematic cultivation of tobacco and vine begun. The exquisite Muscat wine of Samos was exported mainly in Germany, Holland and France while the tobacco in the USA and Germany.
The tobacco industry flourished until the economic crisis of 1930. In 1932 there were public tobacco factories in the port of Vathi, in Tigani (Pythagorio) and in Neo Karlovassi. In Karlovassi 40 small and large leather factories were operating, employing 300-400 workers.
Throughout the era of sail ships Samos had an important role in this industry and with the arrival of the steamships the �Atmoploia Samou� was founded by the commercial house of Iglessis in 1910. The construction of ships had a notable development thanks to the Samian pinewood.
In 1932 small sail ships and mechanized, with internal combustion engines, were being built in different locations of the island. The most important were in Tigani (Pithagorio), in Marathokabos and in Kalabaktassi. It is estimated that Samos built half of the Greek fleet.
The port of Pithagorio linked Greece with the Dodecanese, which was under Italian occupation and all commerce with the coasts of Asia Minor was conducted through Pythagorio.
During the 2nd world war the Greek and allied forces used Pythagorio for their movement from and to Asia Minor. The people of Samos played a decisive role in the resistance against the German and Italian invaders. With the surrender of Italy the Italian commander of the Kouneo brigade placed his men under the command of Bishop Eirinaios and Greek forces (Ieros Lohos) and latter English forces come to the island from the Middle East.
1st-17th November 1943 elements of Ieros Lohos (The Sacred Band) parachuted successfully while others landed by sea in Samos and organized the defense of the island against the Germans.
The 17th of November 1943 bombarded Samos and especially Pythagorio the port used by the Italians. A lot of people fled to the Monastery of Spiliani. The germans conquered the island but the resistance continued on the mountains until the final liberation of the island.