Why did England become involved in World War 1?
England were sticking up for france!
To be more precise, England declared war on Germany and Austria when the Germans landed on Belgium soil. Belgium was under a treaty from England saying that England will protect Belgium whenever enemy enters the Belgian borders...and since England is allies with France and it was already involved in the war England declared war back to Germany
The main reason for this alliances. Germany had tried to isolate France by making alliances with other countries; however they forgot to renew the treaty, so Russia left them. England signed the Entente Cordiale with France and later Russia joined in and it became the triple Entente. At this point Germany also formed an alliance with Italy and Austria-Hungary; this was the Triple alliance. When Germany kept bullying France, England warned Germany that we would go to war them.