On 27th of April Forge of Empire May Day Festival 2017 starts. Hilde will give you 12 main quests which can be done straight away and then you will be able to get daily quests as it was during Spring Event 2017.
Reward for finishing main quest line is Mighty Maypole (2×3), which can be upgraded to Majestic Maypole (3×3) if you’ll finish all daily quests by May 11, 2017. Official announcement is here.