The difference between Come to pass and Happen

When used as verbs, come to pass means to happen, whereas happen means to occur or take place.

Happen is also adverb with the meaning: maybe, perhaps.

check bellow for the other definitions of Come to pass and Happen

Happen as a verb (intransitive):

To occur or take place.

Examples:

"Let me tell you how it happened."
Happen as a verb (transitive, archaic):

To happen to; to befall.
Happen as a verb (intransitive, _, or, _, impersonal, with infinitive):

To do or occur by chance or unexpectedly.

Examples:

"Take an umbrella in case it happens to rain."

"Do you happen to have an umbrella?"

"I happened to get wet."
Happen as a verb (followed by, _, {{m, on):

or }} To encounter by chance.