Shirts, as we know them now, have evolved into a sophisticated unisex, and one of the most commonly used garment around the early twentieth century. Shirt according to the English fashion is a front open upper body garment with collar and cuff, whereas Americans still consider them as a dress shirt and include t-shirts and polo shirts under more generic definition of shirts.
The oldest shirt discovered so far is a preserved highly sophisticated linen shirt found in a First Dynasty Egyptian tomb at Tarkan, and can be dated back to around 3000 BC.
In the middle ages, the shirt was considered as an undergarment. A plain undyed shirt was worn next to the skin, and was considered indecent for it to reveal. Even in medieval artworks, shirts are visible on humble characters such as farmers, prisoners, or laborers. In 1827 Hannah Montague, an American housewife from New York got tired of having to wash the shirt frequently, which her husband wore, and hence invented detachable collars.
As late as 1879, shirts without anything over them were considered indecent.
Around early nineteenth century couloured shirts started trending, that were a casual dress code for the working class or lower class gentry. By the end of nineteenth century dictionary defined shirt as "of cotton, with linen bosom, wristbands and cuffs prepared for stiffening with starch, the collar and wristbands being usually separate and adjustable".
By 1920s shirts started gaining popularity and established itself as a standard. Gaining a worldwide fame and acceptance, around 1930s the accessories for shirt such as collar stays became popular, which kept the collar points connected to the necktie, keeping them in place.