With tread imperial, impartial pallid Death
knocks at the doors of cottages and palaces.

[Pallida mors æquo pulsat pede pauperum tabernas
Regumque turres.]

Horace (65-8 BC) Roman poet and satirist [Quintus Horacius Flaccus]

Odes [Carmina], Book 1, # 4, l. 13ff (1.4.13-14) (23 BC) [tr. Alexander (1999), “To Lucius Sestius”]
    (Source)

(Source (Latin)). Alternate translations:

Death knocks as boldly at the Rich mans dore
As at the Cottage of the Poore,
[tr. Fanshaw (1666), "To L. Sextius, a Consular Man"]

With equal foot, Rich friend, impartial Fate
Knocks at the Cottage, and the Palace Gate.
[tr. Creech (1684), "He adviseth his Friend to live merrily"]

Pale Death, impartial, walks his round: he knocks at cottage-gate
And palace-portal.
[tr. Conington (1872)]

Pale death knocks at the cottages of the poor, and the palaces of kings, with an impartial foot.
[tr. Smart/Buckley (1853), "To Sextius"]

Death comes alike to all, — to the monarch's lordly hall,
Or the hovel of the beggar, and his summons none shall stay.
[tr. Martin (1864), "To Sestius"]

But all the while, with equal step, pale Death strides on unpausing,
Knocks at thé lowly shed and regal tower.
[tr. Bulwer-Lytton (1870), "To Lucius Sestius"]

Pale death, with impartial step, knocks at the hut of the poor and the towers of kings.
[E.g. (1893)]

The kingly tower alike
And pauper's hut pale Death will strike.
[tr. Gladstone (1894), "To the Rich Sextius"]

Pale Death with foot impartial knocks at poor men's dwellings.
And tow'rs of monarchs.
[tr. Phelps (1897), "To Sestius"]

Pale death with foot impartial strikes at the huts of paupers and
Kings' towers.
[tr. Garnsey (1907), "To Sestius"]

With equal foot pale Pluto knocks at hovels of the poor,
And at the tyrant's towers
[tr. Marshall (1908), "Spring"]

Pale Death with foot impartial knocks at the poor man’s cottage and at princes’ palaces.
[tr. Bennett (Loeb) (1912), "Spring's Lesson"]

Marching with step impartial, Death's pale Presence raps its call
At doors of rich and poor alike.
[tr. Mills (1924)]

Hold! Pale Death, at the poor man's shack and the pasha's palace kicking
Impartially, announces his arrival.
[tr. Michie (1964)]

Death raps his bony knuckles, bleached,
Indifferent, on any man’s door, a palace or a hut.
[tr. Raffel (1983)]

Revenant white-faced Death is walking not knowing whether
He's going to knock at a rich man's door or a poor man's.
[tr. Ferry (1997)]

Pale death knocks with impartial foot, at the door of the poor man’s cottage,
and at the prince’s gate.
[tr. Kline (2015), "Spring"]