I can't recommend these podcasts enough. They're usually about 4 hours (he does 1 every 6 months or so) and very detailed.
He's done series on the Mongol Empire, the collapse of the Roman Republic, the First World War, the Persian empire, and my favorite, Ghosts of the Ostfront. All are uniformly excellent.
The latest one on the Gallic holocaust at the hands of Caesar is really good.
These podcasts reveal to me how little has changed in the world of rulers and politicians.
What Dan Carlin does that is remarkable is bring history to life. I highly recommend this- it's great while you're commuting, or on the outs with your gf/s.o...
His other podcast, Common Sense, is a very good independent political podcast.
For Roman history enthusiasts, Alice Beard's SPQR is a very good book. Mike Duncan (History of Rome) is also doing a new podcast on the fall of the Republic.
It's good to have diversions during what shapes up to be a dark period in Big Blue history.. (:
COMEDY
Last Podcast On The Left
The Crabfeast
Tinfoil Hat
HISTORY
The Dollop
Revisionist History
Hardcore History
POLITICS
Pod Save America
538 Politics
Common Sense
Radio Atlantic
PHILOSOPHY
Wake Up
Philosophize This
Meta Treks
CRIME
Crimetown
S-Town
Most Notorous
Crime Writers On
Insight
Sword and Scale
Serial
Ear Hustle
GENERAL
This American Life
Invisibilia
Get Up On This
The HP Lovecraft Literary Podcast
Myths and Legends
The Secret to Victory
COMEDY
Last Podcast On The Left
The Crabfeast
Tinfoil Hat
HISTORY
The Dollop
Revisionist History
Hardcore History
POLITICS
Pod Save America
538 Politics
Common Sense
Radio Atlantic
PHILOSOPHY
Wake Up
Philosophize This
Meta Treks
CRIME
Crimetown
S-Town
Most Notorous
Crime Writers On
Insight
Sword and Scale
Serial
Ear Hustle
GENERAL
This American Life
Invisibilia
Get Up On This
The HP Lovecraft Literary Podcast
Myths and Legends
The Secret to Victory
I highly recommend Left, Right and Center for politics. It's an hour each week and is the most thoughtful and civilized discussion of politics that I've heard.