I traveled to India last year for a business trip. Indian McD has apparently had vegetarian burger options for decades, including the McVeggie (vegetable patty), McSpicy Paneer (cottage cheese patty) and McAloo Tikki (potato-based patty).
The Indian population is about 40% vegetarian, so this makes sense. Personally, I think the vegetarian burgers tasted incredible, and I wish we had them here.