The stamps of the historical German state of Württemberg, particularly those issued between 1919 and 1920, hold a significant place in philatelic history due to their rarity, aesthetic appeal, and historical value. During this tumultuous post-World War I period, Württemberg, like many other regions, transitioned from a monarchy to a republican form of governance, which was reflected in their postage stamps.

### 1. The **35 Pfennig Brown "Dienstmarken für Gemeindebehörden" Stamp**
This stamp was part of a series intended for official use by municipal authorities, known as "Dienstmarken für Gemeindebehörden" (service stamps for municipal administrations). The 35 Pfennig Brown stamp is particularly notable for its scarcity in mint condition, commonly referred to as **postfris** (unhinged mint). Its usage was limited, and its specialized role in administrative tasks makes it a rare find for collectors today. The distinct brown color and crisp printing provide a vivid snapshot of post-war German state governance.

### 2. The **2 1/2 Pfennig Gray with "Volksstaat Württemberg" Marking**
The **2 1/2 Pfennig Gray stamp** was one of the early stamps marked with "Volksstaat Württemberg," indicating the newly established People's State following the dissolution of the monarchy. The "Volksstaat" series represented a period of socio-political transition. The gray stamp, with its modest denomination, holds historical importance and is highly sought after in postfris condition due to limited production and survival rates. It serves as a symbolic token of the democratic shift in Württemberg’s governance post-1918.

### 3. The **50 Pfennig Lilac with "Volksstaat Württemberg" Marking**
Another key stamp in this collection is the **50 Pfennig Lilac**, also bearing the "Volksstaat Württemberg" imprint. This stamp, like its 2 1/2 Pfennig counterpart, encapsulates the republican aspirations of the era. Its vibrant lilac color and the clear postfris status add to its allure for collectors. As fewer examples in mint condition have withstood the test of time, its value has increased significantly over the decades.

### 4. The **1920 Series Featuring the Stag**
A unique set of stamps issued in 1920 featured a stag, an emblem of the region's rich natural heritage. The **10 Pfennig Lilac**, **20 Pfennig Blue**, and **50 Pfennig Yellow** stamps are distinguished by their intricate depiction of the animal, representing both the nobility and the rustic charm of Württemberg. These stamps, often postfris, symbolize not just administrative change but also regional pride. Their detailed artwork and limited release have made them prized collectibles.

In conclusion, the stamps issued by Württemberg between 1919 and 1920 encapsulate a momentous historical shift, combining political, cultural, and artistic significance. Collectors prize these items for their rarity, their pristine postfris state, and the deep historical stories they tell.