Modifies The Events Calendar plugin event archive to include both present and past events. Also reorders the events so they are in revers chronological order.

the-events-calendar-show-all-events.php

<?php
/**
 * The plugin bootstrap file
 *
 * This file is read by WordPress to generate the plugin information in the plugin
 * admin area. This file also includes all of the dependencies used by the plugin,
 * registers the activation and deactivation functions, and defines a function
 * that starts the plugin.
 *
 * @link              http://example.com
 * @since             0.0.1
 * @package           The_Events_Calendar_Show_All_Events
 *
 * @wordpress-plugin
 * Plugin Name:       The Events Calendar - Show All Events
 * Plugin URI:        https://briannadeleasa.com
 * Description:       Modifies the event archive to include both present and past events.
 * Version:           1.0.0
 * Author:            Brianna Deleasa
 * Author URI:        http://briannadeleasa.com
 * License:           GPL-2.0+
 * License URI:       http://www.gnu.org/licenses/gpl-2.0.txt
 * Text Domain:       the-events-calendar-show-all-events
 * Domain Path:       /languages
 */

// If this file is called directly, abort.
if ( ! defined( 'WPINC' ) ) {
	die;
}

add_action( 'tribe_events_pre_get_posts', 'tecsae_events_date_filter' );
/**
 * Filters the Events archive to include all events, not just present events.
 *
 * @since 1.0.0
 *
 * @param $query object
 * @return null
 */
function tecsae_events_date_filter( $query ) {
	$query->set( 'start_date', '' );
	$query->set( 'order', 'DESC' );
}