Consider the following sentence.

> 
> 彼{かれ}が来{こ}ないことを知{し}りませんでした。
> 
> 
> 

I really get confused in determining the subject.
Which is the correct translation?

1. I did not know that he will not come.
2. He did not know about the absence.

Edit
====

Roughly speaking, most of the available answers said that *the speaker is the person knows about that thing*.

However, today I found almost the same sentence quoted from

*A Handbook of Japanese Grammar Patterns for Teachers and Leaners on page 317-318,*

as follows.

[![enter image description here](https://i.stack.imgur.com/C0lmX.jpg)](https://i.stack.imgur.com/C0lmX.jpg)

[![enter image description here](https://i.stack.imgur.com/STo8s.jpg)](https://i.stack.imgur.com/STo8s.jpg)

Its translation is apparently contrary to the analysis given in the existing answers. 
I am now in a critical position but committing suicide is not my option.