diff --git a/Admin/Install/db.json b/Admin/Install/db.json
index d6037bb..2b145b6 100644
--- a/Admin/Install/db.json
+++ b/Admin/Install/db.json
@@ -54,21 +54,24 @@
             "hr_staff_history_unit": {
                 "name": "hr_staff_history_unit",
                 "type": "INT",
-                "null": false,
+                "null": true,
+                "default": null,
                 "foreignTable": "organization_unit",
                 "foreignKey": "organization_unit_id"
             },
             "hr_staff_history_department": {
                 "name": "hr_staff_history_department",
                 "type": "INT",
-                "null": false,
+                "null": true,
+                "default": null,
                 "foreignTable": "organization_department",
                 "foreignKey": "organization_department_id"
             },
             "hr_staff_history_position": {
                 "name": "hr_staff_history_position",
                 "type": "INT",
-                "null": false,
+                "null": true,
+                "default": null,
                 "foreignTable": "organization_position",
                 "foreignKey": "organization_position_id"
             },
diff --git a/Models/Employee.php b/Models/Employee.php
index 4d67f01..0f5ff2b 100644
--- a/Models/Employee.php
+++ b/Models/Employee.php
@@ -205,6 +205,20 @@ class Employee implements ArrayableInterface, \JsonSerializable
         return $this->companyHistory;
     }
 
+    /**
+     * Add company history to employee
+     *
+     * @param mixed $history Company history
+     *
+     * @return void
+     *
+     * @since 1.0.0
+     */
+    public function addHistory($history) : void
+    {
+        $this->companyHistory[] = $history;
+    }
+
     /**
      * Get newest company history.
      *
diff --git a/Models/EmployeeHistory.php b/Models/EmployeeHistory.php
index 7d43b47..cdef6c0 100644
--- a/Models/EmployeeHistory.php
+++ b/Models/EmployeeHistory.php
@@ -41,17 +41,53 @@ class EmployeeHistory implements ArrayableInterface, \JsonSerializable
      */
     protected int $id = 0;
 
-    private $employee = null;
+    /**
+     * Employee
+     *
+     * @var   int|Employee
+     * @since 1.0.0
+     */
+    private $employee = 0;
 
-    private $unit = 0;
+    /**
+     * Unit
+     *
+     * @var   null|int|Unit
+     * @since 1.0.0
+     */
+    private $unit = null;
 
-    private $department = 0;
+    /**
+     * Department
+     *
+     * @var   null|int|Department
+     * @since 1.0.0
+     */
+    private $department = null;
 
-    private $position = 0;
+    /**
+     * Position
+     *
+     * @var   null|int|Position
+     * @since 1.0.0
+     */
+    private $position = null;
 
-    private $start = null;
+    /**
+     * Start date
+     *
+     * @var   \DateTime
+     * @since 1.0.0
+     */
+    private \DateTime $start;
 
-    private $end = null;
+    /**
+     * End date
+     *
+     * @var   null|\DateTime
+     * @since 1.0.0
+     */
+    private ?\DateTime $end = null;
 
     /**
      * Constructor.
@@ -75,61 +111,159 @@ class EmployeeHistory implements ArrayableInterface, \JsonSerializable
         return $this->id;
     }
 
+    /**
+     * Get the employee this history belongs to
+     *
+     * @return int|Employee
+     *
+     * @since 1.0.0
+     */
     public function getEmployee()
     {
-        return $this->employee ?? new NullEmployee();
+        return empty($this->employee) ? new NullEmployee() : $this->employee;
     }
 
+    /**
+     * Set the employee
+     *
+     * @param int|Employee $employee Employee
+     *
+     * @return void
+     *
+     * @todo maybe only do this in the constructor
+     *
+     * @since 1.0.0
+     */
     public function setEmployee($employee) : void
     {
         $this->employee = $employee;
     }
 
-    public function getPosition() : Position
+    /**
+     * Get the position
+     *
+     * @return int|Position
+     *
+     * @since 1.0.0
+     */
+    public function getPosition()
     {
-        return $this->position ?? new NullPosition();
+        return empty($this->position) ? new NullPosition() : $this->position;
     }
 
+    /**
+     * Set the position
+     *
+     * @param int|Position $position Position
+     *
+     * @return void
+     *
+     * @since 1.0.0
+     */
     public function setPosition($position) : void
     {
         $this->position = $position;
     }
 
-    public function getUnit() : Unit
+    /**
+     * Get the unit
+     *
+     * @return int|Unit
+     *
+     * @since 1.0.0
+     */
+    public function getUnit()
     {
-        return $this->unit ?? new NullUnit();
+        return empty($this->unit) ? new NullUnit() : $this->unit;
     }
 
+    /**
+     * Set the unit
+     *
+     * @param int|Unit $unit Unit
+     *
+     * @return void
+     *
+     * @since 1.0.0
+     */
     public function setUnit($unit) : void
     {
         $this->unit = $unit;
     }
 
-    public function getDepartment() : Department
+    /**
+     * Get the department
+     *
+     * @return int|Department
+     *
+     * @since 1.0.0
+     */
+    public function getDepartment()
     {
-        return $this->department ?? new NullDepartment();
+        return empty($this->department) ? new NullDepartment() : $this->department;
     }
 
+    /**
+     * Set the department
+     *
+     * @param int|Department $department Department
+     *
+     * @return void
+     *
+     * @since 1.0.0
+     */
     public function setDepartment($department) : void
     {
         $this->department = $department;
     }
 
-    public function getStart() : ?\DateTime
+    /**
+     * Get start date
+     *
+     * @return \DateTime
+     *
+     * @since 1.0.0
+     */
+    public function getStart() : \DateTime
     {
         return $this->start;
     }
 
+    /**
+     * Set start date
+     *
+     * @param \DateTime $start Start date
+     *
+     * @return void
+     *
+     * @since 1.0.0
+     */
     public function setStart(\DateTime $start) : void
     {
         $this->start = $start;
     }
 
+    /**
+     * Get end date
+     *
+     * @return null|\DateTime
+     *
+     * @since 1.0.0
+     */
     public function getEnd() : ?\DateTime
     {
         return $this->end;
     }
 
+    /**
+     * Set end date
+     *
+     * @param \DateTime $end End date
+     *
+     * @return void
+     *
+     * @since 1.0.0
+     */
     public function setEnd(\DateTime $end) : void
     {
         $this->end = $end;
diff --git a/Models/EmployeeHistoryMapper.php b/Models/EmployeeHistoryMapper.php
index 3eecd74..f0e66c0 100644
--- a/Models/EmployeeHistoryMapper.php
+++ b/Models/EmployeeHistoryMapper.php
@@ -64,6 +64,10 @@ final class EmployeeHistoryMapper extends DataMapperAbstract
             'mapper' => PositionMapper::class,
             'src'    => 'hr_staff_history_position',
         ],
+        'employee'    => [
+            'mapper' => EmployeeMapper::class,
+            'src'    => 'hr_staff_history_staff',
+        ],
     ];
 
     /**
diff --git a/Theme/Backend/staff-list.tpl.php b/Theme/Backend/staff-list.tpl.php
index 8f84f51..c27001b 100644
--- a/Theme/Backend/staff-list.tpl.php
+++ b/Theme/Backend/staff-list.tpl.php
@@ -42,9 +42,9 @@ echo $this->getData('nav')->render(); ?>
                     <tr data-href="<?= $url; ?>">
                         <td data-label="<?= $this->getHtml('ID', '0', '0') ?>"><a href="<?= $url; ?>"><?= $this->printHtml($value->getId()); ?></a>
                         <td data-label="<?= $this->getHtml('Name') ?>"><a href="<?= $url; ?>"><?= $this->printHtml($value->getProfile()->getAccount()->getName1()); ?></a>
-                        <td><?= $value->getNewestHistory()->getUnit()->getName(); ?>
-                        <td><?= $value->getNewestHistory()->getPosition()->getName(); ?>
-                        <td><?= $value->getNewestHistory()->getDepartment()->getName(); ?>
+                        <td><?= $this->printHtml($value->getNewestHistory()->getUnit()->getName()); ?>
+                        <td><?= $this->printHtml($value->getNewestHistory()->getPosition()->getName()); ?>
+                        <td><?= $this->printHtml($value->getNewestHistory()->getDepartment()->getName()); ?>
                         <td><?= !($value->getNewestHistory() instanceof NullEmployeeHistory) ? $this->getHtml('Active') : $this->getHtml('Inactive'); ?>
                 <?php endforeach; ?>
                 <?php if ($c === 0) : ?>