The ranking of the top YouTubers can change frequently due to shifts in content trends and subscriber counts. However, here are the names of five YouTubers who were widely recognized as some of the most popular and influential creators at that time:

1. PewDiePie (Felix Kjellberg): PewDiePie was one of the most well-known YouTubers globally. He gained fame for his gaming commentary and later diversified his content to include vlogs, meme reviews, and more. With tens of millions of subscribers, PewDiePie's channel has been a dominant force on YouTube.

2. T-Series: T-Series is an Indian music and film production company that became one of the largest YouTube channels. It primarily features music videos, Bollywood songs, and film-related content. T-Series had a fierce subscriber race with PewDiePie for the title of the most-subscribed channel.

3. Cocomelon - Nursery Rhymes: Cocomelon is a children's animation channel known for its catchy nursery rhymes and educational content. It gained immense popularity among parents and children, making it one of the top channels on YouTube.

4. Like Nastya (Anastasia Radzinskaya): Like Nastya is a children's channel featuring videos of a young girl named Nastya and her family engaging in various activities and adventures. It has captured the hearts of young viewers worldwide.

5. SET India: SET India is the YouTube channel of Sony Entertainment Television, featuring a variety of Indian television shows, serials, and other entertainment content. It has a substantial viewership from the Indian subcontinent.

Please note that the rankings and popularity of YouTubers can change rapidly as new creators gain prominence and audience preferences evolve. I recommend checking YouTube's official trending and most-subscribed pages to get the most up-to-date information on popular YouTubers.