import {
	EditorState,
	convertToRaw,
	convertFromHTML,
	convertFromRaw,
	ContentState,
} from "draft-js";
...
constructor(props) {
    super(props);
    this.state = {
      editorState: EditorState.createWithContent(
        ContentState.createFromBlockArray(
          convertFromHTML(
            "<p><strong>My</strong> <em>initial</em> <ins>content</ins>.</p>"
          )
        )
      ),
    };
}
...