From TARDIS Index File, the free Doctor Who reference.

The Latter-Day Pantheon are a group of aliens encountered by the Doctor in 1965 New York City. Their true names are unknown.

Nature and abilities

The Latter-Day Pantheon were completely controlled by the belief of the Humans around them. They had no natural powers or personalities, but are instead shaped by what people believe they should be like.

Even their true form (either smoke or a puddles) might just be what people expect of them. When first discovered, the Latter-Day Pantheon were believed to be gods, so that's what they developed into.

History

At least two groups of these aliens came to Earth in 1965. Though only one survived from the crash-landing in London, five survived the crash in New York City. They were discovered by Alexander Lullington-Smythe who tried to take advantage of their powers, claiming they were gods.

The problem was that the human inhabitants of New York City had far too many contradicting beliefs, meaning that the Latter-Day Pantheon had trouble deciding which ideas to obey. Eventually, they decided to end the Vietnam War, but they were stopped by the US Army before they could go along with their plan. (PDA: Salvation)