Just use WP_QUERY
to achieve that.
<?php if ( have_posts() ) : ?>
<header class="page-header" style="animation-delay: 0.3s; animation-duration: 2s;">
<?php
the_archive_title( '<h1 class="page-title">', '</h1>' );
the_archive_description( '<div class="taxonomy-description">', '</div>' );
?>
</header>
<div id="archive-blog-wrapper" class="archive-blog-wrapper three-columns">
<?php /* Start the Loop */ ?>
<?php
//set up a new query
$category_query=new wp_query( array( 'cat' => 'put your category id here');
while ( $category_query->have_posts() ) : the_post(); ?>
<?php
/* Include the Post-Format-specific template for the content.
* If you want to override this in a child theme, then include a file
* called content-___.php (where ___ is the Post Format name) and that will be used instead.
*/
get_template_part( 'content', get_post_format() );
?>
<?php endwhile; ?>
</div><!-- archive-blog-wrapper -->
<?php rock_star_content_nav( 'nav-below' ); ?>
<?php else : ?>
<?php get_template_part( 'content', 'none' ); ?>
<?php endif; ?>