While researching the oldest clothing companies in America, I saw that Brooks Brothers is usually listed. However, there was ready-to-wear clothing that was worn before 1818. So I reached deeper into Google for tailor shops during The Revolutionary War. After an hour of dilly dallying, I found something even better, the oldest clothing company in the world.
Shumiya Shinbutsuguten Co.
Established nearly 10 centuries ago, it is only the 8th oldest company in all of Japan. (Most of the other ones are hotels.)
This company specializes in religious products for Buddhism. They carry over 4000 different items for different sects, holidays, and rituals. They can also do custom design. Whether it's a turn-key shrine or a full on temple, they've been creating products of all sizes since 1024.
Included in their inventory for centuries - clothing for the monks. samue is the traditional work clothes made of heavy canvas. They usually come in navy, black, or brown. For colder weather, they also provide wool fabrics. For more formal or ceremonial occasions, they can also provides robes out of kimono-quality silk or cotton.
images from Shumiya Co.