Did they have the swastika in World War 1?

Answer 1

No, the Swastika was the symbol of the Nazi party. The party was formed after the great war by disaffected men unhappy at the perceived injustice of the treaty of Versailles and what they saw as the weak Weimar republic.

Yes, the Swastika was used in WW1 by various units. The Swastika was an ancient symbol and the American Indians used it as a good luck symbol. The US 45th Infantry Division wore a shoulder sleeve insignia that included a Swastika because of its association with Oklahoma Indians. (Later it became a Red Diamond with a Yellow Swastika which was changed to a Yellow Thunderbird at the outbreak of WW2---because of its association with the Nazi's.)

The Swastika was painted on several WW1 aircraft. One of France's leading Ace had a large swastika painted on the sides and top of the fuselage behind the cockpit. The Lafeyette Escadrille, composed of Americans who volunteered to fly for the French, had the head of an Indian Chief painted on their aircraft and on the bonnet was a small swastika.

The Finnish national insignia was a Blue Swastika but I'm not sure if it was used during WW1 or after. During WW2 the Finnish national insignia painted on their aircraft was a white circle with a Blue Swastika. It may have been used in WW1.