Justin Timberlake with Futrue sex / Lovestone and then Britney with Blackout

Queen Ciara

Madonna like 10,000 years ago.

for me it was madonnas album 'music' when i first recognized electro pop.

I think Black Eyed Peas

Britney gave bits with 'Toxic' then Rihanna was the leader with 'SOS' evolving to 'Don't Stop The Music' and establishing with 'Disturbia'. Britney followed with 'Womanizer'. Then Lady Gaga took over and made everyone do it.

stargate in the late 90s

Madonna.

Actually Gaga, according to ATRL electro-pop wasn't "mainstream" when she was about to debut but after she took over...well the rest is history

Madonna.

Justin Timberlake made Electro Pop mainstream in the US.

BEP.It was the time when everyone moved on to dance music.Before there were a lot of dance hits.But they didn't dethrone rnb from main genre.

Probably the trend started after Blackout came out. I mean, we had other electro-pop albums prior to Blackout (i.e. Hilary Duff's flawless Dignity, JT's F/L, and some other stuff), but I think it all went in to become a trend after Blackout was released.

Nelly and Timbaland with Loose The Fame was majorly influenced by this album

Madonna,The Queen Of Pop.

ACCORDING TO ATRL

Madonna, Britney, Justin and Nelly.