PHP - Mostrar nombre del mes en español

<?php

require_once 'connected.php';

	$result;

	$conn = dbConnect();

	$sql = 'SELECT start_date, end_date FROM activeDates';

	$result = $conn->query($sql);

	$rows = $result->fetchall();

 ?>

	<div class="table-responsive">

	<table>

						<thead>

							<tr>

								<th></th>

								<th>Dates</th>

							</tr>

						</thead>

		<tbody>

		<?php

			foreach ($rows as $row) {

		?>

							<tr>

								<td>

					 <?php

    $start=new DateTime($row['start_date']);

    $startDay=$start->format('j');

    $startMonth=$start->format('F');

    $startYear=$start->format ('Y');

    $end=new DateTime($row['end_date']);

    $endDay=$end->format('j');

    $endMonth=$end->format('F');

    $endYear=$end->format('Y');

    $s=(

        ($startMonth == $endMonth && $startYear==$endYear) ? "$startDay $startMonth till $endDay $endMonth $startYear" :

            ( ($startMonth!==$endMonth && $startYear==$endYear) ? "$startDay $startMonth till $endDay $endMonth $startYear" :

                ( ($startMonth==$endMonth && $startYear!==$endYear) ? "$startDay $startMonth $startYear till $endDay $endMonth $endYear" :

                                                                     "$startDay $startMonth $startYear till $endDay $endMonth $endYear"

                )

             )

        );

    echo $s.PHP_EOL;

                    ?>

								</td>

							</tr>

		<?php } ?>

setlocale(LC_ALL, 'es_ES');

$monthNum  = 2;

$dateObj   = DateTime::createFromFormat('!m', $monthNum);

$monthName = strftime('%B', $dateObj->getTimestamp());

echo $monthName;

// Retorna February

setlocale(LC_ALL, 'spanish');

$monthNum  = 2;

$dateObj   = DateTime::createFromFormat('!m', $monthNum);

$monthName = strftime('%B', $dateObj->getTimestamp());

echo $monthName;

// Retorna Febrero