text_date can’t save date before 1905

1. Can you provide the code you’re trying with/
2. If you’re using any of the taxonmy_* field types, those don’t save to post meta, they save as terms in the taxonomy. So I’d check your terms list for the taxonomy to see if the values you’re expecting are there.

This is my code. The date input works and does register the dates, except when I try to add a date before 1905. When I save the taxonomy with this date 08/13/1899, I have an empty date field and my term meta is empty too. (but it work for 08/13/1980). The date picker does work and the date format is the good one…

add_action( 'cmb2_admin_init', 'details_taxonomy_metabox' );
function details_taxonomy_metabox() {
	$cmb_term = new_cmb2_box( array(
		'id'               => 'taxonomy_details',
		'title'            => esc_html__( 'Taxomomy Details ', 'cmb2' ),
	'object_types'     => array( 'term' ), 
        'taxonomies'       => array( 'authors' ), 
) );
	$cmb_term->add_field( array(
		'name' => 'Date de naissance',
		'id'   => 'birth-date',
		'type' => 'text_date',
	) );	
}

Not managing to re-create at the moment.

https://cloudup.com/cKSo3iZ1Dkp

Using the code below at least. I had to amend it to get a date range that went that far back. Defaults didn’t cover that many.

add_action( 'cmb2_admin_init', 'details_taxonomy_metabox' );
function details_taxonomy_metabox() {
	$cmb_term = new_cmb2_box( array(
		'id'           => 'taxonomy_details',
		'title'        => esc_html__( 'Taxomomy Details ', 'cmb2' ),
		'object_types' => array( 'term' ),
		'taxonomies'   => array( 'category' ),
	) );
	$cmb_term->add_field( array(
		'name' => 'Date de naissance',
		'id'   => 'birth-date',
		'type' => 'text_date',
		'attributes' => array(
			// CMB2 checks for datepicker override data here:
			'data-datepicker' => json_encode( array(
				'yearRange'       => '-150:+0',
			) ),
		),
	) );
}